Burned Rats Research Articles

Erythropoietin Alleviates Burn-induced Muscle Wasting.

Background: Burn injury induces long-term skeletal muscle pathology. We hypothesized EPO could attenuate burn-induced muscle fiber atrophy.Methods: Rats were allocated into four groups: a sham burn group, an untreated burn group subjected to third degree hind paw burn, and two burn groups treated with weekly or daily EPO for four weeks. Gastrocnemius muscle was analyzed at four weeks post-burn.Results: EPO attenuated the reduction of mean myofiber cross-sectional area post-burn and the level of the protective effect was no significant difference between two EPO-treated groups (p=0.784). Furthermore, EPO decreased the expression of atrophy-related ubiquitin ligase, atrogin-1, which was up-regulated in response to burn. Compared to untreated burn rats, those receiving weekly or daily EPO groups had less cell apoptosis by TUNEL assay. EPO decreased the expression of cleaved caspase 3 (key factor in the caspase-dependent pathway) and apoptosis-inducing factor (implicated in the caspase-independent pathway) after burn. Furthermore, EPO alleviated connective tissue overproduction following burn via transforming growth factor beta 1-Smad2/3 pathway. Daily EPO group caused significant erythrocytosis compared with untreated burn group but not weekly EPO group.Conclusion: EPO therapy attenuated skeletal muscle apoptosis and fibrosis at four weeks post-burn. Weekly EPO may be a safe and effective option in muscle wasting post-burn.

The Sinergy of Isoquercetin and D-Galacturonic acid of Cyclea barbata Miers extract on the Migration and Apoptosis of Neutrophil in Rat Burn Wound

Second-degree burn is one of acute traumas that has complexities in its healing process; one of which is the disruption of neutrophils activity and function as the initial cellular defense during inflammatory phase. Appropriate wound treatment can modulate the quantity of neutrophils in burn wounds. Cyclea barbata Miers (CBM) is a local plant that has a potential to influence inflammatory process. This study was aimed to determine the polyphenol and monosaccharide contents of CBM and the effect of CBM on neutrophils migration and apoptosis. We used 30 adult male Wistar rats as experimental animals, wich were randomly separated in two groups according the eutanized time. Each group divided in 3 groups (n=5 per group). Cyclea barbata Miers’ content was analyzed using liquid chromatography mass spectrometry (LCMS/MS) method, while neutrophils migration and apoptosis were observed using immunofluorescence assay method. The result of LCMS/MS assay showed that CBM contains isoquercetin (93.83ng/mL) and d-galacturonic acid (0.114ng/mL). Further result showed that CBM extract can decrease neutrophil migration and improve neutrophil apoptosis during the inflammatory phase of the burn wound. This ability may be enabled by the anti-inflammatory and antiradical properties of isoquercetin and DGA in Cyclea barbata Miers. Further study is required to confirm this hypothesis, specially addition of comparasion groups that treated by single compound such as isoquercetin and DGA.

Formulation, Physical Characterization and Wound Healing Activity Evaluation of Carboxymethyl Chitosan-Curcumin Carbomer-Based Hydrogel

The aim of this study was to determine the effect of different concentration of carboxymethyl chitosan and curcumin on physical characteristics and wound healing activity of carboxymethyl chitosan-curcumin hydrogel. Hydrogels were prepared using carbomer as a gelling agent and TEA was added to neutralize the carbomer hydrogel in order to make it swell. The obtained hydrogels were evaluated for its physical characterization such as organoleptic, viscosity, spreadability, drying time, pH, and wound healing activity on the burned wound in Wistar rats. The results showed that higher concentration of carboxymethyl chitosan significantly reduces viscosity and pH while its spreadability and drying time are significantly increased. Curcumin only affected two out of five physical characteristics: organoleptic and pH. Higher concentration of curcumin reduces its pH but statistical analysis showed no interaction between carboxymethyl chitosan and curcumin. The wound healing activity in Wistar rats with 2nd degree burn wound model indicates that carboxymethyl chitosan-curcumin hydrogel can significantly improve wound healing activity in rats compared to control group. Higher concentration of carboxymethyl chitosan can affect the physical characteristics of carboxymethyl chitosan-curcumin hydrogel i.e. a decrease in viscosity and pH, as well as an increase in spreadability and drying time. On the other hand, higher concentration of curcumin only affected the pH of the preparation. In the wound healing activity test, macroscopic observation showed that the combination of carboxymethyl chitosan-curcumin significantly increased the wound healing activity of 2nd degree burn in Wistar rats. However, the use of this hydrogel preparation statistically did not give significant improvement in wound healing process when compared with G1, G2, G3, G4, and positive control. Based on histopathology test results, it can be concluded that after 14 days of treatment the value of collagen deposition and PMN between groups 1, 2, 3, 4, and positive control and intergroup replication (1, 2, 3, 4, and positive controls) are in uniformity which indicates that the wound has undergone healing process. In addition, the four groups possess better results than negative controls which didn’t receive any treatment.

MIR-190B Alleviates Cell Autophagy and Burn-Induced Skeletal Muscle Wasting via Modulating PHLPP1/Akt/FoxO3A Signaling Pathway.

Cell autophagy is an important material recycling process and is involved in regulating many vital activities under both physiological and pathological conditions. However, the mechanism of autophagy regulating burn-induced skeletal muscle wasting still needs to be elucidated. The rat burn model with 30% total body surface area and L6 cell line were used in this study. An immunofluorescence assay was used to detect autophagic levels. MicroRNA array and real-time PCR were employed to measure miR-190b levels, and its influence on PH domain and leucine-rich repeat protein phosphatase 1 (PHLPP1) protein translation was estimated using luciferase reporter assay. The expression levels of autophagy-related proteins were analyzed by Western blot. Skeletal muscle wasting was evaluated by the ratio of tibias anterior muscle weight to body weight. Our study demonstrates that burn injury promotes expression of the autophagy-related proteins light chain 3 (LC3) and Beclin-1, suppresses expression of Akt and Forkhead box O (FoxO) 3a protein phosphorylation, and increases PHLPP1 protein level which is required for Akt dephosphorylation. miR-190b, the regulator of PHLPP1 protein translation, also significantly decreases after burn injury. Ectopic expression of miR-190b in L6 myoblast cell downregulates PHLPP1 protein expression, elevates Akt and FoxO3a phosphorylation, and subsequently reduces cell autophagy. Finally, suppressing autophagy with 3-methyladenine represses the protein expression of LC3 and Beclin-1 and mitigates burn-induced skeletal muscle wasting. Burn injury induced skeletal muscle cell autophagy and subsequently resulted in skeletal muscle wasting via regulating miR-190b/PHLPP1/Akt/FoxO3a signaling pathway.

Identification of Metagenomics Structure and Function Associated With Temporal Changes in Rat (Rattus norvegicus) Skin Microbiome During Health and Cutaneous Burn.

The cutaneous skin microbiome is host to a vast ensemble of resident microbes that provide essential capabilities including protection of skin barrier integrity and modulation of the host immune response. Cutaneous burn-injury promotes alteration of cutaneous and systemic immune response that can affect both commensal and pathogenic microbes. A cross-sectional study of a limited number of burn patients revealed a difference in the bacteriome of burned versus control participants. Temporal changes of the skin microbiome during health and cutaneous burn-injury remains largely unknown. Furthermore, how this microbial shift relates to community function in the collective metagenome remain elusive. Due to cost considerations and reduced healing time, rodents are frequently used in burn research, despite inherent physiological differences between rodents and human skin. Using a rat burn model, a longitudinal study was conducted to characterize the rat skin bacterial residents and associated community functions in states of health (n = 30) (sham-burned) and when compromised by burn-injury (n = 24). To address the knowledge gap, traumatic thermal injury and disruption of cutaneous surface is associated with genus-level changes in the microbiota, reduced bacterial richness, and altered representation of bacterial genes and associated predicted functions across different skin microbial communities. These findings demonstrate that, upon burn-injury, there is a shift in diversity of the skin's organismal assemblages, yielding a core microbiome that is distinct at the genome and functional level. Moreover, deviations from the core community correlate with temporal changes post-injury and community transition from the state of cutaneous health to disease (burn-injury).

Falkenbergia rufolanosa polysaccharide – Poly(vinyl alcohol) composite films: A promising wound healing agent against dermal laser burns in rats

This work was conducted to evaluate the compatibility between physicochemical, antioxidant and morphological properties of polysaccharide (FRP) extracted from red marine alga Falkenbergia rufolanosa reinforced by poly (vinyl alcohol) (PVA) composed films at different ratios of FRP/PVA: F1 (70:30), F2 (50:50), F3 (30:70) and PVA (100% PVA) and the potential wound healing effects. As assessed, FRP/PVA prepared films were heterogeneous, slightly opaque with a rough surface as ascertained by Fourier transform infrared spectroscopy, scanning electron microscopy and colorimetric parameters. Even, X-ray diffraction and glass transition results revealed a semi-crystalline structure of FRP composed films which decreased with increasing PVA ratios. The antioxidant activities of composite films depicted that F1 exhibited the highest antioxidant activity in vitro. Therefore, F1 was found to promote significantly the wound healing, after eight days of treatment, evidenced by higher wound appearance scores and a higher content of collagen (885.12 ± 20.35 mg/g of tissue) confirmed by histological examination, when compared with control, CYTOL BASIC® and PVA-treated groups. All together, the marine-derived polysaccharide gave a substantial pledge for the development of biodegradable films as a potent antioxidant material and a promising agent for tissue regeneration.

Burn-Induced Impairment of Ileal Muscle Contractility Is Associated with Increased Extracellular Matrix Components

IntroductionSevere burns lead to marked impairment of gastrointestinal motility, such as delayed gastric emptying and small and large intestinal ileus. However, the cellular mechanism of these pathologic changes remains largely unknown. MethodsMale Sprague Dawley rats approximately 3 months old and weighing 300–350 g were randomized to either a 60% total body surface area full-thickness scald burn or sham procedure and were sacrificed 24 h after the procedure. Gastric emptying, gastric antrum contractility ileal smooth muscle contractility, and colonic contractility were measured. Muscularis externa was isolated from the ileal segment to prepare smooth muscle protein extracts for Western blot analysis. ResultsCompared with sham controls, the baseline rhythmic contractile activities of the antral, ileal, and colonic smooth muscle strips were impaired in the burned rats. Simultaneously, our data showed that ileal muscularis ECM proteins fibronectin and laminin were significantly up-regulated in burned rats compared with sham rats. TGF-β signaling is an important stimulating factor for ECM protein expression. Our results revealed that TGF-β signaling was activated in the ileal muscle of burned rats evidenced by the activation of Smad2/3 expression and phosphorylation. In addition, the total and phosphorylated AKT, which is an important downstream factor of ECM signaling in smooth muscle cells, was also up-regulated in burned rats’ ileal muscle. Notably, these changes were not seen in the colonic or gastric tissues. ConclusionDeposition of fibrosis-related proteins after severe burn is contributors to decreased small intestinal motility.

Ghrelin abates bacterial translocation following burn injury by improving gastric emptying.

In severe burns, increased intestinal permeability facilitates bacterial translocation, resulting in systemic endotoxemia and multi- organ failure. We investigated the role of burn-induced gastrointestinal dysmotility (BIGD) in promoting bacterial translocation following burn injury, and the protective effect of ghrelin in this process. We assessed gastric emptying (GE%) and intestinal transit (IT by geometric center "GC") in a 60% total body surface area scald burn rat model and measured bacterial counts in mesenteric lymph nodes (MLN) and distal small intestine by colony-forming unit per gram of tissue (CFU/g). A group of animals was treated with ghrelin or saline after burn. Scald burn was associated with a significant delay in GE (62%±4% vs 74%±4%; P=.02) and a trend of delay in intestinal transit (GC: 5.5±0.1 vs 5.8±0.2; P=.09). Concurrently, there was a marginal increase in small intestinal bacterial overgrowth (6×105 vs 2×105 CFU/g; P=.05) and significant translocation to MLN (2×102 vs 4×101 ; P=.03). We observed a negative correlation between GE and intestinal bacterial overgrowth (rs =-0.61; P=.002) and between IT and translocation (rs =-0.63; P=.004). Ghrelin administration significantly accelerated GE following burn injury (91%±3% vs 62%±4; P=.03), reduced small intestinal bacterial overgrowth, and completely inhibited translocation to MLN (0.0 vs 5×102 ; P=.01). Burn-induced gastrointestinal dysmotility is correlated with the systemic translocation of gram-negative gut bacteria that are implicated in multiple organ failure in burn patients. Therapeutic interventions to restore BIGD are warranted (Neurogastroenterol Motil, 2012, 24, 78).

The Wound Healing Effect of Doxycycline after Corneal Alkali Burn in Rats.

Purpose To evaluate the wound healing effect of doxycycline and its underlying mechanisms in a rat model of corneal alkali burn. Methods Male SD rats were administered 1.0 N NaOH in the right cornea for 25 seconds and randomly divided into the doxycycline group and the control group, with 84 rats in each group. 1.0 g·L−1 doxycycline eye drops (doxycycline group) or vehicle (control group) was topically instilled onto the rat cornea after chemical injury. Three days, 7 days, and 14 days after alkali burn, microscopy was used to observe corneal wound healing by fluorescein staining and the degree of corneal opacity. The expression of transforming growth factor-beta 1 (TGF-β1) and matrix metalloproteinase-9 (MMP-9) was detected by RT-PCR and ELISA, alpha-smooth muscle actin (a-SMA) levels were measured by immunofluorescent staining, and Western blot assays for TGF-β1, a-SMA, and nuclear factor-kappa B (NF-κB) were also performed. Results Corneal wound healing and corneal opacity scores were better in the doxycycline group than in the control group. Three, 7, and 14 days after corneal alkali burn, a significant increase in TGF-β1 was observed in corneas from the control group, compared with the corneas from the doxycycline group (P < 0.05). The corneal levels of MMP-9 in the doxycycline group were lower than those in the control group 3 days and 7 days after alkali burn (P < 0.05). In addition, doxycycline inhibited α-SMA expression and suppressed NF-κB expression. Conclusion Doxycycline treatment promoted corneal healing and reduced corneal opacity in SD rats. Doxycycline protected the cornea from alkali burn injury by reducing TGF-β1, MMP-9, NF-κB, and α-SMA expression.

The effect of allogenic human Wharton's jelly stem cells seeded onto acellular dermal matrix in healing of rat burn wounds.

Various methods were introduced to overcome the autograft shortage in burn wound care, including cell transplantation and tissue engineering. To evaluate the healing effect of allogenic human Wharton's jelly stem cells (hWJSCs) seeded onto acellular dermal matrix (ADM) in rat burn injuries. Human Wharton's jelly stem cells provided from umbilical cord tissue were characterized before transplantation, and the growth kinetic was determined. Skin samples from cosmetic surgeries were used for preparation of ADM. Forty male Sprague Dawley rats were randomly divided into 4 equal groups. Third-degree burn was induced for all animals by exposing to hot water using a 2cm ring for 10seconds. Group 1 was burned rats that did not receive any treatment. After burn injury, the second group received silver sulfadiazine (SSD), the third group was treated just by using ADM, and the fourth group received 2×106 hWJSCs seeded onto ADM. The animals were euthanized for histologic evaluation after 7, 14, and 21days. Human Wharton's jelly stem cells were characterized to be spindle shape and positive for osteogenic and adipogenic induction and for mesenchymal markers but lacked hematopoietic markers. Population doubling time (PDT) was 40.1hours with an increasing growth trend until day 6th. Macro- and microscopically, the healing was mild in ADM group and moderate in ADM+hWJSCs group after 21days. Allogenic hWJSCs seeded onto ADM improved the healing process in burn wounds denoting to their therapeutic and anti-inflammatory effects in burn wounds that can be added to the literature.

NOX2 Expression Is Increased in Keratinocytes After Burn Injury

Reepithelialization is crucial for effective wound repair in burn wounds. Reactive oxygen species (ROS) have shown to be important in this. Recent studies suggest that NOX proteins produce ROS in keratinocytes. In the present study, we have studied NOX proteins in burn wounds, including the effect of C1-esterase inhibitor (C1inh) hereon, which is the endogenous inhibitor of complement activity whereof we have shown previously that it also increased the rate of reepithelialization in burn wounds. Skin tissue derived from healthy control Wistar rats (n = 6) were compared with burn-injured rats, with (n = 7) or without C1inh treatment (n = 7). After 14 days, rats were terminated. From the burn-injured rats, the entire wound and nonburned skin from the hind leg, that is, internal control was excised. From the control rats, dorsal skin was excised. In these skin samples, NOX2 and NOX4 were analyzed immunohistochemically. In nonburned rats, NOX2 was found in keratinocytes in both the basal layer and suprabasal layer of the epidermis; and the number of NOX2-positive keratinocytes was 367/mm2 (254–378). In burned rats, the number of NOX2-positive keratinocytes was significantly increased in the newly forming epidermis in the burned area to 1019/mm2 (649–1172), especially in the suprabasal layer, but significantly decreased in remote nonburned skin to 22/mm2 (6–89). C1inh treatment counteracted these changes in epidermal NOX2 expression in burned rats, both in the burned area as in remote nonburned skin. No NOX4 expression was found in the epidermis in none of the groups. NOX2 expression was increased in keratinocytes in newly forming epidermis after burn injury. C1inh, a drug that increases the rate of reepithelialization, counteracted this effect. These results suggest a role for NOX2 in the reepithelialization of burn wounds.

Effect of Hydrogen Sulfide on the Mitogen-Activated Protein Kinase Signaling Pathway in Cultured Skin Macrophages of Burned Rats

BackgroundThis study aims to investigate the effect of hydrogen sulfide on the mitogen-activated protein kinases signaling pathway in in vitro cultured skin macrophages of burned rats. Materials and methodsThirteen healthy Sprague–Dawley rats were divided into five groups: normal control group, burned control group, sodium hydrogen sulfide group, glibenclamide group, and sodium hydrogen sulfide + glibenclamide group. The burned rats were made into a deep II° 5% total body surface area flame burn injury model. The skin basement macrophages were separated from the skin of normal rats and the wound skin of burned rats and cultured. At 1, 6, and 12 h after intervention, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 protein levels were detected by Western blot, and ERK, p38, and JNK messenger RNA (mRNA) levels were detected by reverse transcription polymerase chain reaction. ResultsDifferences in ERK, p38, and JNK mRNA and protein levels between the normal control group and burned control group were statistically significant (P < 0.05). At the same time point, the ERK, p38, and JNK mRNA and protein levels in the NaSH group were different from those in other groups, and the differences were statistically significant (P < 0.05). ConclusionsHydrogen sulfide has a regulatory effect on ERK, JNK, and p38 in the mitogen-activated protein kinases signaling pathway in macrophages of burned rats.

Histopathological Changes of Organs (Lungs, Liver, Kidney, and Brain) After Using Two Types of AgiCoat and Acticoat Nanosilver Dressings on Deep Second-Degree Burn in Rat

Prevention of infections is a very important issue in treating the burn wounds. The nanosilver dressings have many promising advantages, but absorption of silver ions and its adverse effects to the body were always a question. The aim of this study was to compare Silver serum levels and acute toxic effects of nanosilver on histopathology of organs (lungs, liver, kidney, spleen, and brain) in two types of AgiCoat and Acticoat (nanosilver) dressings on second-degree deep burn in rat. This is an experimental study conducted in our animal laboratory. We divided 24 Sprague-Dawley male rats weighing 300 to 350 randomly into two groups. After anesthesia, a second deep-degree burn was made over dorsal skins of rats by standard method. For group A, Agicoat and, for group B, Acticoat dressings were used. The dressings were changed every 3 days with AgiCoat and Acticoat, respectively. After 14 days, we got blood samples and tissue samples taken from heart, liver, kidneys, spleen, lungs, and brain and a sample from dorsal skin of the rat for histopathological examinations. The results showed that the levels of serum silver in both groups were significantly higher than the standard level (1.22 part per million (PM); AgiCoat, P = .017; Acticoat, P = .000), but there was no significant difference between the groups (P = .551). Examination of the relationship between the level of serum silver and histopathological changes in liver showed that hepatotoxicity of AgiCoat was higher compared with Acticoat and the difference was significant (P = .002). There were no pathological changes in brain, kidneys, spleen, heart, and lungs. Wound healing was faster in Acticoat group. The nanosilver dressings can cause toxicity in liver but not in kidney, brain, spleen, heart, and lungs. Liver pathology and hepatotoxicity were more prominent in AgiCoat group. Wound healing was faster in Acticoat group.

Human Bone Marrow Mesenchymal Stem Cell Conditioned Medium Promotes Wound Healing in Deep Second-Degree Burns in Male Rats

Burn wound treatment is difficult and one of the most challenging problems in the clinic. Researchers have examined the applications of mesenchymal stem cells as a cell-based therapy for skin regeneration. But the role of human bone marrow mesenchymal stem cell conditioned medium (hBM-MSC-CM) in the treatment of burn injury remains unclear. This research aims at detecting whether hBM-MSC-CM can increase the wound healing of deep second-degree burns in male rats. In this study, 32 adult male rats per each time point were randomly divided into four groups: (1) control group, (2) sham group (DMEM), (3) common treatment group (CT), and (4) conditioned media group (CM). A 3 × 3 cm circular burn was created on the back of the rats. On postsurgical days 7, 15, and 28, the wound closure area of each wound was measured and then the skin samples were removed and analyzed using stereological methods. Wound closure area was significantly increased in the CM and CT groups on the 15th and the 28th day after burn injury compared to the control and DMEM groups. The stereological parameters and immunohistochemistry analysis of the wounds revealed significantly improved healing in the CM group compared to the control and other groups. It is concluded that these findings indicate that hBM-MSC-CM promotes skin wound healing by increasing cell proliferation, regulating collagen synthesis and collagen composition, and inducing angiogenesis at the injury site.

Effects of Carvacrol in an Experimentally Induced Esophageal Burn Model: Expression of VEGF and Caspase-3 Proteins

Introduction We investigated the therapeutic effects of carvacrol in an experimental esophageal burn rat model with immunohistochemical techniques. Materials and Methods: Three groups were included in this study, composed of eight Wistar albino rats each. The control group was given 1 mL 0.9% (wt/vol) NaCl; esophageal burns were induced in groups 2 and 3 by administration of 1 mL 40% NaOH in the distal 2 cm of the esophagus. The treatment group was administered 75 mg/kg carvacrol in 2 mL 0.9% NaCl for 10 days. After a routine histological examination of the tissues, sections were stained with vascular endothelial growth factor (VEGF) and caspase-3 for immunohistochemical analysis and were examined under a light microscope. Results: In the control group, there were regular cells in the cornified epithelial tissue and cylindrical cells in the basal layer, which faced toward the apical surface in the mitotic phase. The burn group displayed wide degeneration, necrosis, and abundant apoptotic cells in the epithelial tissue as well as intense inflammatory cell infiltration. In the treatment group, there was an increase in mitotic activity in the basal cells of the epithelial layer and degenerative changes, but a preserved epithelial layer and significant cornified structures. The treatment group showed positive caspase-3 expression in some apoptotic cells within the epithelial layer and in connective tissue, and there were only a small number of degenerated cells in the muscle layer. Additionally, in the treatment group, VEGF expression was evident in small numbers of inflammatory cells in the papillary region of the epithelium, and in dilated vascular endothelial cells. Conclusions: Carvacrol may contribute to a reduction in fibrosis by decreasing inflammation and preventing cell apoptosis.

Role of mammalian target of rapamycin in regulating HIF-1α and vascular endothelial growth factor signals in glaucoma

Hypoxia inducible factor subtype 1α (HIF-1α) in retinal tissues is involved in the development of glaucoma. This study examined the role played by mammalian target of rapamycin (mTOR) in regulating expression of HIF-1α and its downstream pathway, vascular endothelial growth factor (VEGF). Glaucoma was induced by chronic elevation of intraocular pressure using laser burns in rats. ELISA and western blot analysis were employed to determine the levels of HIF-1α, VEGF and mTOR in retinal tissues of eyes with high intraocular pressure. In results, HIF-1α, VEGF and VEGF receptor subtype 2 were increased in laser eyes. The p-mTOR, mTOR-mediated phosphorylation of 4E-binding protein 4, p70 ribosomal S6 protein kinase 1 were also amplified in retina of laser eyes. Blocking mTOR using rapamycin attenuated HIF-1α-VEGF pathways, accompanied with downregulation of apoptotic Caspase-3. Our data revealed potential signalling pathways engaged in the development of glaucoma, including the activation of mTOR and HIF-1α-VEGF mechanism.

English

Mangosteen has several important elements for biological activities such as antioxidant, anti-inflammatory, anti-bacterial and anti-cancer. There are γ-mangostin, α- mangostin, flavonoids, saponins, and tannins which could stimulate the collagen deposition and accelerate wound healing process. Burn injury cause deep wound in the skin and often cause cicatrix and keloid scar on the skin. However, there is limited information about role of mangosteen in skin wound healing after burn injury. Fifty 10 week-old male rats, were subjected to burn injury using automatic temperature control. Burn injury was created by direct contact of hot plate (170°C) for 15 seconds on rats’ inter scapula region. We elaborated the role of extract mangosteen in skin wound healing by applying daily gel contain with active compound derived from mangosteen. There was no significant weight change during treatment period. We observed that there was significant increase of Epidermal Growth Factors (EGF) expression in 14 as shown in immunohistochemistry and confirmed by western blot protein results. Taken together, mangosteen peel extractmediated changes in the expression of growth factors in burned rat skins. Mangosteen peel extract might have a role in the acceleration of skin wound healing.

Serum Level of Musclin Is Elevated Following Severe Burn.

Muscle wasting induced by severe burn worsens clinical outcomes is associated with hyperglycemia. A novel muscle-specific secretory factor, musclin, was reported to regulate glucose metabolism with a homologous sequence of natriuretic peptides. The purpose of the study was to investigate musclin expression in response to burn injury in both human and animal models. Serum was collected from 13 adult burn patients and circulating levels of musclin protein were measured via elisa. The cytokine profile was measured by Bio-Plex multiple immunoassay. Following the clinical study, we used a burn rat model with 40% TBSA to study the time course of musclin expression till day 14. Rat serum and muscle tissue sample were harvested. Finally, an in vitro study was applied to investigate whether the muscle cell C2C12 myoblast expressed musclin under 10% burn serum stimulation. Pearson analysis showed that there was a significant positive correlation of musclin expression to total body surface area of burn in patients (P &= .038). Musclin expression was significantly positively correlated with IL-4, IL-7, IL-12, and IL-13 in burn patients' serum (P < .05). In the animal study, we found that the musclin level evaluated at 6 hours and 1 day in burn rat serum (P < .05). In vitro, musclin mRNA expression significantly increased with burn serum stimulation at 24 hours (P < .05). In conclusion, serum level of musclin elevated both in human patients and burn animals; musclin was correlated with the severity of burn injury as well as with an elevated cytokine profile in patients; burn serum-stimulated musclin expression in vitro further identified the resource of musclin expression after burn.

Comparative study on the effects of heated brass bar and scald methods in experimental skin burn in rat

Experimental burn can be inflicted by various means, and each method affects the healing processes. To date, several methods have been developed, but their standardization is difficult. We aimed to compare two experimental methods, heated brass bar, and scalding, to provide an in-depth understanding of their limitations and errors. Scald burn is afflicted by pouring 2.5 cc of boiling water (95 °C) into a firm rubber ring (2 cm diameter) on the dorsal surface of a rat skin for 15 s. The other experimental model is performed by bringing a brass bar (2 cm diameter) heated to 95 °C in boiling water in contact with the surface of the skin for 15 s. The clinical course of healing was evaluated macroscopically for 7 days, and then microscopically. The scald burn produced a uniform wound with the same depth of tissue damage without any marked inflammation and hemorrhage. The scab formation and the extent of granulation tissue, as well as re-epithelialization, were the same in all rats and the lesions healed uniformly. Compared with scald, burns of various depths were induced by the heated brass bar and the burn area did not heal uniformly. Widespread hemorrhage and microabscess were common in this group without any sign of scab formation or re-epithelialization. This study highlights the benefits of scald method in comparison with the heated brass bar.

The effects of Beeswax, Olive oil and Butter impregnated bandage on burn wound healing

BackgroundBeeswax, Olive oil and Butter (BOB) are nutritive products that could support wound healing by adsorption to bandage. This study demonstrated the therapeutic effects of BOB on second degree burn. MethodsSecond degree burn model was created in rats. Experimental groups were assigned to Healthy, Burn, Silver Sulfadiazine (SS) and BOB. The effects of BOB were evaluated on skin regeneration, vesicles and bullae and fibroblast activity by histopathological analyses and wound contraction percent were determined. Transforming Growth Factor-Beta1 (TGF-β1) and Vascular Endothelial Growth Factor-alpha (VEGF-α) mRNA expressions were analyzed with Real Time-Polymerase Chain Reaction. All parameters analyzed at 3rd, 7th, 14th days. ResultsThe BOB treatment increased TGF-β1 and VEGF-α expressions compared to Burn group. The histopathological analyses showed that epidermis and dermis layers injured due to burn. BOB treatment augmented the regeneration of these layers and increased fibroblast activity and keratinization which are play important role on the new blood vessels production. Also with the BOB treatment we showed wound contraction levels were higher than Burn and SS treatment. ConclusionThis study demonstrated that beeswax–olive oil–butter mixture impregnated bandage treatment in a second-degree burn rat model improved burn wound healing and encouraged skin renewal via modulating tissue TGF-β1 and VEGF-α.