Burn Injury In Rats Research Articles

Battery-free and AI-enabled multiplexed sensor patches for wound monitoring.

Wound healing is a dynamic process with multiple phases. Rapid profiling and quantitative characterization of inflammation and infection remain challenging. We report a paper-like battery-free in situ AI-enabled multiplexed (PETAL) sensor for holistic wound assessment by leveraging deep learning algorithms. This sensor consists of a wax-printed paper panel with five colorimetric sensors for temperature, pH, trimethylamine, uric acid, and moisture. Sensor images captured by a mobile phone were analyzed by neural network-based machine learning algorithms to determine healing status. For ex situ detection via exudates collected from rat perturbed wounds and burn wounds, the PETAL sensor can classify healing versus nonhealing status with an accuracy as high as 97%. With the sensor patches attached on rat burn wound models, in situ monitoring of wound progression or severity is demonstrated. This PETAL sensor allows early warning of adverse events, which could trigger immediate clinical intervention to facilitate wound care management.

Enhanced Healing of Cutaneous Burn Wounds in Diabetic Rats: with the administration of β-glucans Having Dual Significant Properties- Antioxidant Effects and Phenotypic Transition

The aim of this study was to evaluate the effects of β-Glucans obtained from Saccharomyces cerevisiae on the wound healing process in diabetic rats induced with streptozotocin. The investigation evaluated multiple wound healing parameters, such as the closure of the wound, alongside the assessment of CD68 and CD163 proteins, which function as indicators for M1 and M2 macrophages, respectively. The study also investigated the effects of β-Glucans on inflammatory markers, specifically IL-6 and IL-10. Additionally, the researchers analysed hydroxyproline and hexosamine levels, and performed histopathological examinations. The current study examined the anti-inflammatory effects by employing the paw edoema and cotton pellet induced granuloma methods. The findings of this study suggest that β-Glucans exhibit therapeutic properties that may have potential benefits in the treatment of burn injuries among individuals diagnosed with diabetes. These substances facilitate expedited healing of burn wounds, augment tensile strength, and exhibit properties that combat oxidation and inflammation. In addition, β-Glucans have been shown to enhance the levels of tissue hydroxyproline and hexosamine, leading to the enhancement of collagen synthesis and the development of the extracellular matrix in burn wounds of individuals with diabetes. Importantly, -Glucans have a beneficial impact on the inflammatory stage of burn wound healing without inhibiting the generation of pro-inflammatory mediators, particularly interleukin-6 (IL-6). By increasing production of the anti-inflammatory mediator interleukin-10 (IL-10), they also aid in the proliferation process. By increasing CD163 expression and decreasing CD68 expression, the research showed that -Glucans had a substantial effect in promoting the switch from the M1 to M2 phenotype at the appropriate moment. The end result is faster recovery from burn injuries in diabetic rats. Overall, the results support beta-glucans' therapeutic potential in the effective management of burn wounds in diabetic patients. Keywords: β-Glucans, Diabetic burn wound, Biochemical analysis, Phenotypic Transition, Western blot analysis, wound healing,

578 Impact of Acellular Fish Skin on Wound Healing in a Standardized Pre-Clinical Model

Abstract Introduction Acellular fish skin has proven to be effective in acute and chronic wound healing. Multiple human studies have to date demonstrated that products from acellular skin grafts accelerate wound healing and are efficacious, safe and cost-effective. Here we wanted to investigate the effects of acellular fish skin on wound healing in a pig model. Methods The primary aim of this study was to investigate the effects of acellular fish skin on wound healing progression in a full thickness skin defect pig model. The superiority of fish skin was tested in a standardized pig model and compared to normal wound healing (without acellular fish skin grafts) (n=6). The experiments were carried out in male landrace pigs with a mean weight of 28.8 +/- 2.8 kg at the start of the study. The experiment lasted for 21 days. Wound documentation, thermography, photo-documentation and wound perfusion were carried out 5, 9, 14 and 21 days post wounding. Results Clinical evaluation of the wounds showed that there were no major differences between the different dressings on day 5 post wounding. On the next evaluation days ( day 9, 14 and 21 post wounding) the acellular fish skin showed rapid epithelialization with minimal wound contraction, when compared to untreated control wounds, which showed significant signs of contraction (i.e. star-like wound appearance). Wound area measurements clearly showed that wound size upon treatment with the acellular fish skin and the untreated control rapidly and significantly decreased through contraction of untreated controls. However, wound perfusion seemed to be affected by the treatment with acellular fish skin. Thermography at day 9 and 14 showed higher surface temperature in treated wounds (d9 and d14; p = 0.0005), followed by a trend towards increased oxygenation and perfusion, analyzed by laser speckle and hyperspectral imaging. Conclusions Acellular fish skin seems to provide fast wound healing and counteract wound contraction. Untreated wounds showed a slight trend of faster healing, but showed significant signs of wound contraction which points towards wound healing by contraction but not by epithelialization. This contraction was not observed in wounds treated with acellular fish skin. Applicability of Research to Practice Standardized preclinical models give valuable insights to the mechanisms of wound healing. Porcine in vivo models are of special interest as the porcine skin is highly similar to human skin with regard to anatomical and physiological structures. Therefore, data generated in such models, as described here, show a high rate of translatability to the human situation.

579 Histopathological Changes in the Endocrine Pancreas of Rats During the Acute Period of Burns

Abstract Introduction Severe burn victims experience a systemic inflammatory response and a hypermetabolic response. Presence of hyperglycemia, even with concurrent hyperinsulinism, is indicative of insufficient insulin secretion from beta cells to overcome the glycemia. However, the underlying molecular mechanisms of beta-cell failure in patients with acquired insulin resistance after burn trauma are not clearly understood. Our aim in this study was to describe the histopathological changes in the pancreatic islets secondary to severe burns in an experimental animal model. Methods Fourteen Wistar albino rats were randomly divided into 2 groups: the sham group and the burn group. A full-thickness burn model was designed to induce a burn of 25% total body surface area. Seven days after burn induction and sham procedure, pancreatectomy was performed. Pancreatic tissues were examined under light microscopy, and islet size and cellularity were calculated. Results The histopathologic examination was unremarkable, but the mean number of islets per pancreatic tissue was lower in the burn group than in the sham group. We observed a significant difference in the mean number of cells per one islet between the 2 groups, with the cell count higher in the burn group (P < .05). Conclusions During the acute phase of burn injury in rats, we observed a decrease in the number of pancreatic islets with remarkable hypercellularity. Further studies are needed to determine the histological and cellular basis of these changes. Applicability of Research to Practice Major burn injury causes severe alterations in beta-cell mass, which increases and decreases both function and mass to maintain the glycemic level within a very narrow physiological range. Patients with acute and prolonged hyperglycemia can have complications leading to impaired wound healing, increased skin graft loss, increased muscle protein catabolism, increased incidence of infections, and mortality. Therefore, a detailed understanding of the pancreatic changes under different preexisting conditions and therapeutic interventions in the context of a major burn trauma might guide treatment options.

Effects of Bioactive Compound, Ginsenoside Rb1 on Burn Wounds Healing in Diabetic Rats: Influencing M1 to M2 Phenotypic Trans

Panax notoginseng (P.notoginseng) has been used traditionally to treat traumatic injuries. Ginsenoside Rb1, a key active ingredient derived from P.notoginseng, has received a lot of interest due to its anti-inflammatory, bacteriostatic, and growth-promoting effects on cells. The therapeutic benefits of ginsenoside Rb1 on burn wounds in STZ-induced diabetic rats, as well as the probable underlying processes, were investigated in this work. The skin wound healing effect of ginsenoside Rb1 (0.25 and 0.5% w/w) in a rat model of burn wounds in diabetic rats was observed at various time points after treatment. On days 5 and 19 following treatment, immunohistochemistry and Western blot analysis for Interleukin 1 beta (IL-1β), Tumour necrosis factor-α (TNF-α), Cluster of Differentiation 68 (CD68) and Cluster of Differentiation 163 (CD163) of biological tissues were done. The macroscopic observation was used to track the healing of skin wounds at various periods. The protein expression of CD68 and CD163, which serve as M1 and M2 macrophage markers, was examined in detail. More notably, the ability of ginsenoside Rb1 to alter inflammatory markers (IL-6) and anti-inflammatory markers (IL-10), influence on hydroxyproline and hexosamine was observed. As indicated by increased CD163 (M2) and reduced CD68 (M1) on day 5, ginsenoside Rb1 effectively flips the M1 to M2 phenotypic transition at the right time to improve burn wound healing in diabetic rats. Ginsenoside Rb1 (0.5 % w/w) treatment showed higher tensile strength, anti-inflammatory properties, antioxidant properties, increased tissue hexosamine and hydroxyproline levels. Skin tissue morphology was significantly improved following 19 days of ginsenoside Rb1 (0.5% w/w) therapy, according to hematoxylin-eosin and Masson’s trichrome staining. Furthermore, Ginsenoside Rb1 (0.5% w/w) favoured the inflammatory phase of burn wound healing (IL-6), assisted the proliferation process (IL-10) and had considerably lower expression of IL-1β and TNF-α on the later stage of wound healing. Overall, the data showed that ginsenoside Rb1 (0.5 % w/w) accelerates burn wound healing in diabetic rats through a mechanism that may be linked to the M1 to M2 phenotypic shift.

Comparison of healing effects of aloe vera gel and aloe vera leaf pulp extract on burn-wound rats

Aloe Vera has anti-inflammatory, anti-oxidant, anti-viral, and anti-microbial properties. It has been demonstrated that Aloe Vera use could accelerate healing of burn injuries in rats. The current study evaluates the effects of Aloe Vera gel and Aloe Vera leaf pulp extract (LPE) alone and together with silver sulfadiazine on third degree burn wound injuries in rats. In an experimental study, 70 male Wistar rats weighing 200–250 g were divided into 7 groups to receive topical placebo, silver sulfadiazine, Aloe Vera gel, Aloe Vera LPE and their combination. Treatment results were evaluated according to wound healing on days 3, 10, and 21 and according to pathologic findings on day 21. Wound size differed significantly between groups on day 3 (p= 0.001), day 10 (p= 0.001), and day 21 (p= 0.001). The study's findings indicate that Aloe Vera gel alone, compared to LPE, and the combination of Aloe Vera gel or LPE with silver sulfadiazine had a more significant reduction in wound size. The combined treatment of Aloe Vera LPE and silver sulfadiazine has shown several advantages, including enhanced epithelialization and reduced cell infiltration, granulation tissue formation, and vascularization in the treatment of burns. However, additional research is necessary to determine the most effective treatment for third-degree burns.

Effects of functional poly(ethylene terephthalate) nanofibers modified with sericin-capped silver nanoparticles on histopathological changes in parenchymal organs and oxidative stress in a rat burn wound model

In this study, it was aimed to investigate the effect of a poly(ethylene terephthalate)-g-poly(hydroxyethyl methacrylate) (PET-g-HEMA) nanofiber wound dressing modified with sericin-coated silver nanoparticles (S-AgNPs) on internal organs, oxidative stress, and biochemical parameters. To establish a burn model, the backs of anesthetized rats were shaved and then third-degree burns were created with a round-bottomed stainless steel rod 2 cm in diameter kept in 100 °C water for 20 seconds. The wounds of the negative control group (G1) were covered with standard bandages; the wounds of the positive control group (G2) were covered with silvercel, used as burn wound material; and the wounds of the experimental group (G3) were covered with PET-based dressing material. Histopathological changes in organs (liver, kidneys, heart, pancreas, lungs), total oxidant status (TOS), total antioxidant status (TAS), nitric oxide (NO), and biochemical parameters (serum aspartate aminotransferase [AST], alanine aminotransferase [ALT], gamma glutamyl transpeptidase [GGT], creatine kinase, lactate dehydrogenase [LDH], total protein, albumin, globulin, urea) were examined. Compared with the G1 group, plasma AST, ALT, and GGT levels were found to be significantly decreased in G2 and G3 (P<0.001). Plasma TAS was found to be significantly increased in G2 and G3 compared to G1 (P<0.05). Compared to the G1 group, degenerative and necrotic changes in the liver, kidneys, and pancreas were found to be significantly reduced in G2 and G3 (P<0.05). In conclusion, this work demonstrates that the synthesized PET-based wound dressing material has the capacity to be used commercially.

Effect of Aloe vera extract in post-burn skin repair in rats

Background: Burn injury is a global health problem that is most often caused by heat. A burn injury can cause high morbidity and mortality and requires high cost. Therefore, the use of plants as an herbal medicine has the potential to be developed in Indonesia. Aloe vera contains various active ingredients that help the wound healing process, such as glucomannan and acemannan which have the effects on the proliferation of macrophages, fibroblasts, and re-epithelialization. This study aimed to determine the effect of Aloe vera extract in repairing post-burn skin in rats that were analyzed from the number of macrophages, fibroblasts, and epidermal thickness. Methods: This is an experimental study with a posttest-only control group design using 54 Rattus norvegicus Wistar strain rats. The sampling method was simple random sampling consisting of 3 groups, i.e., I. standard group, which were normal rats; II. negative control group, which were given second-degree burns and treated with gel base (without Aloe vera extract); III. treatment groups, which were given second-degree burns and treated with Aloe vera extract gel. Each group was subdivided into three smaller groups (n = 6) according to the time the lesions were evaluated. Skin tissue samplings were carried out on days 3, 14, and 21 after injury to observe the number of macrophages, fibroblasts, and epidermal thickness. Results: There were significant differences in the mean number of macrophages, number of fibroblasts, and epidermal thickness in all groups (p<0.05). Conclusion: Based on the result of the study, Aloe vera extract could fasten the healing process of 2nd degree burn wound in rats.

Characteristics of endotoxemia in different ways of treatment of experimental burn in rats

The article evaluates the dynamics of toxemia and detoxification capabilities of various wound dressings in thermal burn injury in rats in the experiment. A wound dressing based on collagen and chitosan Collachit® and a membrane wound dressing containing a hyperosmolar solution in the cavity were compared. Studies of the dynamics of toxemia in burn disease after experimental thermal injury were carried out on Wistar rats (n=20). Analysis of the results of the study was carried out on the basis of clinical, morphological and biochemical parameters of the peripheral blood of rats with experimental burn injury. The study of the morphology of blood cells is carried out according to generally accepted methods. Biochemical manifestations of endotoxemia are established by the dynamics of ALT, AST, urea, creatinine. In the 1st group of rats (n=10), the Collachit® wound dressing was applied. In the 2nd group (n=10), a semi -permeable membrane filled with a hyperosmolar solution, constituting a necrolytic enzyme, was fixed on the surface of the burn. As a result, it was found that burn toxemia in rats proceeded in 2 phases and was accompanied by depression, food refusal, leukocytosis, increased LII, liver transferases, creatinine and urea. Hematological deviations were characterized by non-uniform dynamics, corresponding to the phase of burn toxemia with maximum increases on days 1-2 and 5-7, a fall on days 3-4, and days 8-10. Hematological manifestations of toxemia depended on the method of treatment and were less pronounced with the use of membrane wound dressings than with collachitis. External signs of toxemia do not in all cases correspond to the hematological and biochemical profile of toxemia, which indicates the possibility of a latent course of burn disease with some methods of treatment. The applied wound dressings had a pronounced antiseptic efficacy, characterized by the absence of purulent-inflammatory complications over the entire period of the experiment.

Bisacurone gel ameliorated burn wounds in experimental rats via its anti-inflammatory, antioxidant, and angiogenic properties.

To investigate putative mechanism of wound healing for chitosan-based bisacurone gel against secondary burn wounds in rats. A second-degree burn wound with an open flame using mixed fuel (2 mL, 20 seconds) was induced in Sprague Dawley rats (male, 180-220 g, n = 15, each) followed by topical treatments with either vehicle control (white petroleum gel, 1%), silver sulfadiazine (1%) or bisacurone gel (2.5, 5, or 10%) for 20 days. Wound contraction rate and paw withdrawal threshold were monitored on various days. Oxidative stress (superoxide dismutase, glutathione, malondialdehyde, and nitric oxide), pro-inflammatory cytokines (tumour necrosis factor-alpha, interleukins by enzyme-linked immunosorbent assay), growth factors (transforming growth factor-β, vascular endothelial growth factor C using real time polymerase chain reaction and Western blot assay) levels, and histology of wound skin were assessed at the end. Bisacurone gel showed 98.72% drug release with a 420.90-442.70 cps viscosity. Bisacurone gel (5 and 10%) significantly (p < 0.05) improved wound contraction rate and paw withdrawal threshold. Bisacurone gel attenuated oxidative stress, pro-inflammatory cytokines, and water content. It also enhanced angiogenesis (hydroxyproline and growth factor) and granulation in wound tissue than vehicle control. These findings suggested that bisacurone gel can be a potential candidate to treat burn wounds via its anti-inflammatory, antioxidant, and angiogenic properties.

Metformin Improves Burn Wound Healing by Modulating Microenvironmental Fibroblasts and Macrophages.

Metformin, a biguanide, exerts different functions through various signaling pathways. In order to investigate the function and mechanism of metformin in burn wounds, we established burn rat models, subcutaneously injected metformin to treat the wounds, and observed the morphologies and the expression of collagen I, collagen III, fibronectin, and pro-inflammatory markers. In vitro experiments were performed to investigate the effects of metformin on the proliferation, migration, and collagen I synthesis of the mouse embryonic fibroblast (NIH 3T3) cell line and on the proliferation, apoptosis, and immune response of the mouse mononuclear macrophage (RAW 264.7) cell line. Finally, we studied the regulatory effects of metformin on a co-culture of RAW 264.7/NIH 3T3 cells. We found that 100 mM of metformin reduced dermal thickness, collagen I deposition, and mRNA expression of IL1β and CCL2 in rat burn wounds. In vitro experiments revealed that metformin inhibited the proliferation of NIH 3T3 and RAW 264.7 cells. Metformin attenuated NIH 3T3 cell migration via the AMPK/mTOR pathway and attenuated collagen I synthesis through the TGFβ1/Smad3 pathway. Metformin inhibited the apoptosis of RAW 264.7 cells induced by 10 μg/mL LPS. Metformin downregulated the mRNA expression of IL1β and CCL2 in RAW 264.7 cells under 1 μg/mL LPS induction by inhibiting NF-κB p65 phosphorylation. In a RAW 264.7/NIH 3T3 co-culture, metformin attenuated collagen I synthesis in NIH 3T3 cells by inhibiting RAW 264.7 paracrine secretion of TGF-β1. This provides new evidence related to the development of metformin for potentially improving burn wound healing.

The nonopioid cholinergic agonist GTS-21 mitigates morphine-induced aggravation of burn injury pain together with inhibition of spinal microglia activation in young rats

BackgroundRepetitive opioid use does not always alleviate basal pain, procedural pain, or both after burn injury. Mitigation of burn injury-site pain can be achieved by GTS-21 stimulation of α7-acetylcholine nicotinic receptors (α7AChRs) and reduced microglia activation in rat. We tested the hypothesis that morphine exaggerates burn injury-site pain and GTS-21 alleviates both morphine-induced aggravated burn injury pain and microglia activation. MethodsYoung rats with dorsal paw burn injury or sham-burn received intraperitoneal saline, morphine, GTS-21, or a combination twice daily for 14 days. Ipsilateral plantar pain thresholds were tested every other day before morning drugs from days 0–20. Spinal microglia activation, evidenced as pain-transducer (tumour necrosis factor-α [TNF-α], interleukin [IL]-6, IL-1β, nuclear factor kappa B [NF-κB], Toll-like receptor 4 [TLR4]) expression, was examined using immunohistochemistry and immunoblot. In cultured microglia, morphine-induced cytokine expression was measured (quantitative polymerase chain reaction/enzyme-linked immunosorbent assay [qPCR/ELISA]). ResultsMorphine aggravated allodynia at day 5 in sham-burn (P=0.039, n=8–11) but significantly aggravated burn injury site allodynia by day 3 (P=0.010, n=8–11). Microgliosis paralleled nociceptive behaviour changes where burn injury with morphine had highest microgliosis compared with burn injury, morphine alone, or controls (number of cells per field [SD]: 33.8 [2.4], 18.0 [4.1], 8.2 [1.9], and 4.8 [2.0], respectively; P<0.001, n=4–5]. GTS-21 reversed the morphine-induced pain component in sham-burn and burn injury rats together with reduced microgliosis and spinal pain-transducer expression (TNF-α, IL-6, IL-1β, NF-κB, and TLR4). Morphine-exposed microglial cells showed increased cytokine expression, which was mitigated by GTS-21. ConclusionsMorphine or burn injury alone increases pain together with microgliosis and pain-transducer expression. Morphine administration augments burn injury-site nociception sooner and aggravated spinal microgliosis and inflammatory pain-transducer expression. GTS-21 has the potential to treat morphine-induced pain in burn injury.

Correction to: Study of Novel Platelet Lysate Film-Forming Spray on Burn Wounds in Rats

Correction to: Study of Novel Platelet Lysate Film-Forming Spray on Burn Wounds in Rats

Phytochemical profile, in vivo anti-inflammatory and wound healing activities of the aqueous extract from aerial parts of Cistus ladanifer L

Cistus ladanifer L. is a Mediterranean shrub, well recognized for its many pharmacological properties. The present study aimed to investigate the phytochemical profile, the in vivo anti-inflammatory and the wound healing activities of the aqueous extract from its aerial parts (AECL). The in vivo anti-inflammatory and the wound healing properties were evaluated by carrageenan-induced paw edema (CAECL) and burn wound in rats, respectively. The results showed that six compounds belonging to flavonoids and tannins were identified in the AECL extract. Moreover, the AECL administrated orally at a dose of 500 mg/kg significantly reduced edema with a percentage of 72 % in terms of inflammation inhibition, using indomethacin as reference drug. On the other hand, when administrated topically, both doses of CAECL cream (5 % and 10 %) manifested a significant anti-inflammatory action using diclofenac as reference drug with a percentage reduction of inflammation that reached 85 % (CAECL-10). As far as wound healing is concerned, the CAECL showed higher effect at a dose of 10 % (CAECL-10) producing a wound contraction of 96 %, similar to that of the reference drug. The findings of the present study indicate that the aqueous extract from aerial parts of Cistus ladanifer L. display strongly anti-inflammatory and wound healing effects to be advantageously used for medical purposes.

Effects of Drug-Free Pectin Hydrogel Films on Thermal Burn Wounds in Streptozotocin-Induced Diabetic Rats.

This study aims to examine the influence of drug-free pectin hydrogel films on partial-thickness burn wounds using streptozotocin-induced diabetic rats as the animal model. Thirty male Sprague Dawley rats were included in the wound healing study, and scalding water was used to produce wounds in the dorsum region of the rats. Two different formulations of pectin hydrogel films, PH 2.5% and PH 5%, were prepared using a solvent evaporation method. MEBO® (moist exposed burn ointment), a commercial herbal formulation was used as a positive control. The progress of the wound healing was observed and compared between untreated normal rats, untreated diabetic rats, diabetic rats treated with MEBO®, diabetic rats treated with PH 2.5%, and diabetic rats treated with PH 5%. The results showed that diabetic rats treated with PH 5% healed faster than the untreated diabetic rats and diabetic rats treated with PH 2.5%. Interestingly, the diabetic rats treated with PH 5% healed as well as diabetic rats treated with MEBO®, where wounds were healed entirely on day 20. Nevertheless, both PH 2.5% and PH 5% showed a greater zone of inhibition than MEBO® when tested against Staphylococcus aureus.

Optimization, characterization and in vivo evaluation of mupirocin nanocrystals for topical administration

Treatment of infectious skin conditions resulting from wounds and burns with topical antibiotics is challenging, particularly those caused by methicillin-resistant Staphylococcus aureus bacteria (MRSA). This is due to the formation of bacterial biofilms characterized by antimicrobial resistance. Mupirocin (MP), a widely used topical antibiotic, is active against gram-positive bacteria including MRSA. However, MP suffers from sub-optimal therapeutic efficacy due to its poor water-solubility and the significant rise in MP-resistant S. aureus. In this study, the physico-chemical characteristics of MP were modified through nanocrystallization to improve its therapeutic efficacy for the treatment of skin infections. Mupirocin-nanocrystals (MP-NC) were prepared using a nanoprecipitation technique and optimized using a D-optimal response surface design. The optimization of MP-NC produced ultra-small monodisperse spherical particles with a mean diameter of 70 nm and a polydispersity index of 0.2. The design resulted in two optimal MP-NC formulations that were evaluated by performing series of in vitro, ex vivo, microbiological, and in vivo studies. In-vitro results showed a 10-fold increase in the saturation solubility and a 9-fold increase in the dissolution rate of MP-NC. Ex vivo permeation studies, using pig ears skin, showed a 2-fold increase in the dermal deposition of MP-NC with the highest drug deposition occurring at 500-µm skin depth. Moreover, the optimal MP-NC formulations were lyophilized and incorporated into a 2% w/w cream. Microbiological studies revealed a 16-fold decrease in the minimum inhibitory concentration and the minimum bactericidal concentration of MP-NC. In vivo studies, using a rat excision burn wound model, demonstrated rapid and complete healing of infected burn wounds in rats treated with MP-NC cream in comparison to marketed Avoban ointment. Our results suggest that nanocrystallization of MP may provide an avenue through which higher levels of a topically applied MP can be permeated into the skin to reach relevant infectious areas and exert potential local antibacterial effects.

Low-Temperature Storage of Placenta Affects Anti-Inflammatory and Wound Healing Properties of Its Extracts

Here we have studied the effect of low-temperature storage of the placenta at different temperatures on anti-inflammatory activity of its extracts in cell models of erythrocyte thermohemolysis and adenosine-5’-diphosphate-induced platelet aggregation. The wound-healing effect of cryopreserved placental extracts was also evaluated in rat thermal burn model. When preserving placenta for up to a month, the temperature of storage was shown to cause no significant impact on the percentage of inhibition of erythrocyte thermohemolysis and platelet aggregation by the extracts. Placental storage for three months at –20°C decreased anti-inflammatory activity of its extracts, and led to its complete loss during 6 months. Placental cryopreservation at –196°C enabled to preserve the anti-inflammatory and wound-healing activity. The cryopreserved placenta-derived extracts showed a pronounced positive effect on reparative process at third-degree (B) skin burn injury in rats.

Globularia arabica Methanolic Leaf Extract Has Higher Efficacy on Burn Wound Healing in Diabetic Rats Compared to Malva slyvestries Methanolic Leaf Extract.

This study aimed to see how effective Globularia arabica and Malva slyvestries-based cream formulations were at healing scald burn wounds in rats. Depending on ointment, preparations of 1%, 5%, and 10% w/w were created. For comparison, an ointment base and a regular burn cream composed soframycine were utilized. Rats introduced a burn by solidifying equipment at 100°C on a 14-mm2 shaved dorsal region. A deep second-degree burn was created, and the percentage of wound contraction was measured over the next 15 days. The rats were euthanized on days 8 and 15, and histological slides were prepared using hematoxylin and eosin staining. Compared to the control group, there was a substantial increase in wound contraction and a significant decrease in the duration of epithelialization in the based ointment-treated groups. However, as paralleled to Globularia arabica, significant (P < .05) results were observed with 10% Globularia arabica cream, whereas Malva slyverstries indicate minimal healing. Soframycine causes a substantial increase in wound contraction (P < .05). Soframycine cream with 10% Globularia arabica therapy resulted in practically complete re-epithelialization and re-structuring of wound tissue on histological examination, whereas Malva slyversries treatment resulted in low epithelization during treatment days. The findings suggest that Globularia arabica-based cream has the wound-healing capability.

Effect of intermittent fasting on saving zone of stasis in burn wounds in rats

BackgroundIntermittent Fasting (IF) has proved to have various positive effects on life span, diseases, and healing of tissues in rodents. We evaluated the protective effect of fasting in maintaining the ischemic zones in burn wounds. MethodsIn this study, 20 rats were divided into two groups where the IF rats were deprived of food for three months. Burn wounds were created by burn comb model on the back of all rats. On days 3 and 21 after injury, five rats in each group were euthanized whereby samples were collected for histopathological, immunohistochemical (Bcl2, P53 and VEGF), and biochemical (MDA, TAC, HP) evaluations. ResultsHistopathological analysis revealed epithelial layer and zone of ischemia remained viable in the intermittent fasting group on day 3. On the 21st day, epithelialization, angiogenesis, inflammation, fibrocyte-fibroblast, and collagen density were different in the ischemic and necrotic zones between the control and intermittent fasting groups (p<0.05). We found no statistical differences in Bcl2, P53, VEGF, MDA, TAC, and HP on day 3 between the intermittent fasting and control groups. ConclusionsIntermittent fasting before burn wounds reduces tissue damage caused by ischemia and enhanced the viability of cells in zone of stasis. It also accelerated wound healing by increasing epithelialization and collagen production in the skin and regulating inflammatory responses. This intervention appears to be related to better collagen arrangement and angiogenesis.

Schizophyllum commune-derived Chitin Glucan Complex Wound Dressing: Antibacterial Activity and Wound Healing Properties in a Second Degree Burn Animal Model

ABSTRACT The chitin-glucan complex (CGC) consists of β-glucan and chitin with covalant bonds. CGC with biodegradable, biocompatible, antioxidant, and antibacterial properties is a powerful agent in wound healing. Schizophyllum commune is a source of these metabolite. This study aims to optimize the preparation of CGC nanofibers by electrospinning. Optimal conditions were selected for fabricating nanofibers (10% PVA solution, 2% CGC solution, 0.29 g gelatin, and 2.3 mL of acetic acid) with 17 kV, 900 rpm, and a feed rate of 0.3 mL/min. SEM showed uniform nanofibers with a diameter of 210 ± 71 nm and 56% porosity. FTIR investigates possible interactions between components. CGC/PVA/Gelatin nanofibers are hydrophilic. The tensile strength and Young’s modulus reached 4.223, 2.2092 Mpa, respectively. CGC/PVA/Gelatin nanofibers inhibit the growth of E. coli and S. aureus by 25% and 78% after 24 hours, respectively. These nanofibers are nontoxic to fibroblast cells and improve their proliferation and adhesion. CGC/PVA/Gelatin nanofibers were used to cover grade 2 burn wounds in male Wistar rats. Morphometric results showed that the wound healing rate is 86% in the nanofibers treated group (p< 0.05) and 58% and 49% in the positive and negative control groups. S. commune CGC nanofibers can be used as wound dressings.