scholarly journals Structural transformations of thermal burn wounds in rats under the influence of Semax and Selank neuropeptides

2020 ◽  
Vol 7 (6) ◽  
pp. 321-331
Author(s):  
A. K. Azhikova ◽  
B. V. Feldman ◽  
A. A. Andreeva ◽  
D. D. Teply ◽  
M. A. Samotrueva ◽  
...  

The morphological features of the skin of rats under the stress exposure, such as burn injury and against the background of the correction by the drugs of the peptide structure, have been studied.The aim of the study was to investigate the regulatory effect of the neuropeptide drugs Semax (Met-Glu-His-Phe-Pro-Gly-Pro) and Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro) under the conditions of thermal burn exposure.Materials and methods. The object of the study was integumentary tissues (skin, subcutaneous tissue) of laboratory non-linear male rats (n = 36) excised from the thermal injury zone. A thermal burn of the skin had been caused by the application of a copper object in the interscapular in the interscapular dorsal area. Starting from the first day after the injury, neuropeptide drugs Semax (Met-Glu-His-Phe-ProGly-Pro) and Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro) had been administered intraperitoneally at the doses of 100 μg/kg daily during the entire period of the experiment. To assess the condition of the skin tissues, histological sections 5–6 μm thick were prepareв, stained afterwards with hematoxylin and eosin. The consistency of the systemic effect of the neuropeptide drugs was estimated by a change in some indicators of the immune system.Results. The thermal exposure led to the development of significant degenerative and dystrophic changes in the skin. The recovery of the burn wounds on rats’ skins proceeded according to the type of the delayed partial reparative regeneration, accompanied by destructive phenomena and the formation of the scar tissue.Under the influence of the drugs based on the regulatory peptides of Semax (Met-Glu-His-Phe-Pro-Gly-Pro) and Selank (Thr-Lys-Pro-Arg-ProGly-Pro), the recovery of burn wounds in rats proceeded more intensively, compared with the animals from the group without any correction. This fact was confirmed by the earlier signs of the beginning of the reparative skin regeneration: the restriction of destructive processes within the epidermis and dermis, the absence of purulent-necrotic complications, the initial phases of granulation and epithelization, an early scab rejection and a partial closure of the defect.Conclusion. The use of the neuropeptide drugs Semax and Selank as systemic remedies for the correction of wound skin defects in experimental animals proves their polypotent effectiveness, expands the therapeutic possibilities and opens up new prospects for their use. 

Author(s):  
Vladislav A Dolgachev ◽  
Susan Ciotti ◽  
Emma Liechty ◽  
Benjamin Levi ◽  
Stewart C Wang ◽  
...  

Abstract Objective Burn wound progression is an inflammation driven process where an initial partial-thickness thermal burn wound can evolve over time to a full-thickness injury. We have developed an oil-in-water nanoemulsion formulation (NB-201) containing benzalkonium chloride for use in burn wounds that is antimicrobial and potentially inhibits burn wound progression. We used a porcine burn injury model to evaluate the effect of topical nanoemulsion treatment on burn wound conversion and healing. Methods Anesthetized swine received thermal burn wounds using a 25cm 2 surface area copper bar heated to 80 oC. Three different concentrations of NB-201 (10%, 20%, or 40% nanoemulsion), silver sulfadiazine cream or saline were applied to burned skin immediately after injury and on days 1, 2, 4, 7, 10, 14, and 18 post-injury. Digital images and skin biopsies were taken at each dressing change. Skin biopsy samples were stained for histological evaluation and graded. Skin tissue samples were also assayed for mediators of inflammation. Results Dermal treatment with NB-201 diminished thermal burn wound conversion to a full-thickness injury as determined by both histological and visual evaluation. Comparison of epithelial restoration on day 21 showed that 77.8% of the nanoemulsion treated wounds had an epidermal injury score of 0 compared to 16.7% of the silver sulfadiazine treated burns (p=0.01). Silver sulfadiazine cream and saline treated wounds (controls) converted to full-thickness burns by day 4. Histological evaluation revealed reduced inflammation and evidence of skin injury in NB-201 treated sites compared to control wounds. The nanoemulsion treated wounds often healed with complete regrowth of epithelium and no loss of hair follicles (NB-201: 4.8±2.1, saline: 0±0, silver sulfadiazine: 0±0 hair follicles per 4mm biopsy section, p<0.05). Production of inflammatory mediators and sequestration of neutrophils were also inhibited by NB-201. Conclusions Topically applied NB-201 prevented the progression of a partial-thickness burn wound to full-thickness injury and was associated with a concurrent decrease in dermal inflammation.


2019 ◽  
Vol 9 (3-4) ◽  
pp. 163-171
Author(s):  
Heba A. Yassa ◽  
Randa T. Hanna ◽  
Hala Zein El Abdin

Background: Determination of time passed since burn injury in the living is critical in forensic science. Autophagy biomarkers and vitronectin can play an important role in determination of the age of burn injuries through their levels in the tissue. Objective: The aim of this study was to investigate the role of autophagy biomarkers in dating burn injury and to correlate them with the histopathological effects of deep second-degree thermal burn. Method: Fifty-four male rats were used in this study after infliction of second-degree thermal burns to their skin. Samples were taken from them after 30 minutes and one, four, 24, 48, and 72 hours following burn to be examined histologically and also for autophagy biomarkers and vitronectin. Results: Significant reduction in the autophagy biomarkers (p < 0.001) over the first 24 hours then began to increase but still not reach the normal level up to 72 hours after burn. Vitronectin level increased after burn infliction 1.5-fold after first hour, then up to four-fold after four hours and after that began to decline but still did not reach the normal level up to 72 hours. Conclusion: Autophagy biomarkers can be used as a forensic tool in determination of the time passed since burn infliction in living.


2018 ◽  
Vol 24 (4) ◽  
pp. 53-57
Author(s):  
K.S. Volkov ◽  
S.Yu. Muha

Deep, large area of thermal trauma of the skin leads to significant morphofunctional changes in organs in the composition of the burned organism. However, condition of the central organ of the male reproductive system - testicle after burns and, especially, in the treatment of thermally damaged areas of the skin remain poorly understood. The purpose of this study was to establish an ultrastructural re-organization of testis germinal epithelium cells in the stages of toxemia and septicotoxemia following an experimental thermal trauma when using xenograft skin substrate. The studies were carried out on 35 sexually mature white male rats, which were divided into three groups: 1 - intact animals (5 rats), 2 - animals with burn injury (15 rats), 3 - animals with burn injury, for which were used xenograft skin substrate (15 rats). The burn was applied under ketamine anesthesia with copper plates, heated in boiling water, on 1820% shaved body surface of animals. Early necrectomy of the damaged areas of skin was carried out 1 day after the thermal burn. The formed wounds were covered with cryo-lyophilized xenograft skin substrate. Experimental animals were decapitated at 7, 14 and 21 days of the experiment (early, late toxemia and septicotoxemia). The material sampling for electron microscopy was carried out in accordance with a generally accepted methodology. It is established that in the stage of early toxemia (7 days of experiment) there are adaptive-compensatory changes and signs of destruction of spermatogenic cells of testis. In the stages of late toxemia and septicotoxemia (14 and 21 days of the trial), significant destructive changes occur in all components of the seminiferous tubules of the organ. Electron microscopically found that the closure of the burn wound after the early necrectomy of cryo-lyophilized xenograft skin substrate in severe experimental burn injury in the early stages of the experiment significantly reduces the damage of testis germinal epithelium of experimental animals and activates regenerative processes. This contributes to a significant improvement in the ultrastructure of the components of the convoluted tubules of the organ in the late stages of the experiment.


Author(s):  
Л.Л. Алиев ◽  
О.А. Писарева ◽  
А.А. Арутюнян ◽  
Д.В. Чегодарь ◽  
А.В. Кубышкин ◽  
...  

Актуальность. Ожоговые повреждения кожи, в частности термические ожоги, во всем мире являются общепризнанной социально-медицинской проблемой. Согласно данным ВОЗ, на долю термических ожогов кожи и ассоциированных с ними осложнений приходится около 15% среди общего числа травматических повреждений мирного времени. Несмотря на быстрое внедрение новых методов лечения ожогов кожи, вопрос эффективности этиопатогенетически обоснованной терапии остается актуальным и дискутабельным. Цель. Определить степень и характер изменений неспецифических протеиназ и их ингибиторов в сыворотке крови и супернатантах гомогенатов кожи у крыс линии Wistar с моделью термического ожога кожи II степени, а также на фоне применения биокомпозиции на основе наночастиц серебра, стабилизированных в растворе альгинатом натрия, и ингибитора протеиназ апротинина для оценки модификации течения воспалительного процесса. Методы. Проведено две серии экспериментальных исследований на белых крысах самцах линии Wistar: в первой серии оценивали динамику изменений в протеиназ-ингибиторной системе сыворотки крови и супернатантах гомогенатов кожи крыс без коррекции, а во второй серии изучали вышеперечисленные изменения на фоне медикаментозной коррекции. В сыворотке и супернатантах гомогенатов энзиматическими методами определяли трипсиноподобную активность (ТПА), эластазоподобную активность (ЭПА), антитриптическую активность (АТА) и кислотостабильные ингибиторы (КСИ); белок определяли методом Лоури. Результаты. В статье представлены результаты динамических изменений показателей неспецифических протеиназ и их ингибиторов при моделировании термического ожога II степени на 100 белых крысах линии Wistar. Наиболее эффективным вариантом экспериментальной коррекции нарушений протеиназ-ингибиторного гомеостаза является сочетанное применение аппликаций с раствором наносеребра и апротинина. Заключение. Полученные данные изменений протеолитической активности отражают характер выраженности воспалительного процесса и могут свидетельствовать о развитии деструктивных изменений в кожных покровах крыс. Установлено, что на локальном уровне дисбаланс неспецифических протеиназ и их ингибиторов характеризуется активацией протеиназ на фоне истощения ингибиторного потенциала, в то время как на системном - повышение протеолитической активности сопровождается ростом уровней ингибиторов, что подтверждает целесообразность локальной терапии ожогов с применением ингибиторов протеиназ. Наиболее эффективным вариантом коррекции нарушений протеиназ-ингибиторного гомеостаза является сочетанное применение аппликаций с раствором наносеребра и апротинина. Background. Burn injuries of the skin, specifically thermal burns, are internationally recognized as an important social and medical issue. According to statistical data of the World Health Organization thermal skin burns and their complications account for approximately 15% of all peacetime traumatic injuries. Despite the rapid development of new therapies for skin burns the effectiveness of etiologically and pathogenetically substantiated therapy remains a relevant and controversial issue. Aim: To determine the degree and nature of changes in nonspecific proteinases and their inhibitors in serum and supernatants of skin homogenates from Wistar rats with second degree deep thermal burn wounds and during the use of a biocomposition based on silver nanoparticles stabilized in a solution with sodium alginate and a proteinase aprotinin inhibitor for modification of the inflammatory process. Methods. Two series of experiments were performed on Wistar male rats: 1) evaluating the dynamics of changes in proteinases and their inhibitors in blood serum and supernatants of rat skin homogenates without correction and 2) studying the above-listed changes during a pharmaceutical correction. The trypsin-like activity (TLA), elastase-like activity (ELA), antitryptic activity (ATA), and acid-stable inhibitors (ASI) were measured in serum and supernatants of homogenates using enzymatic methods; protein concentration was determined by the Lowry method. Results. The article presents dynamic changes in nonspecific proteinases and their inhibitors studied on a model of second degree deep thermal burn wounds in 100 Wistar rats. Combination applications with a solution of nanosilver and aprotinin was the most effective experimental treatment of the proteinase and inhibitor homeostasis disorders. Conclusions. The observed changes in proteolytic activity reflect the nature of inflammatory process and may indicate development of destructive changes in the rat skin and alleviation of inflammation using the experimental treatment. At the local level, the imbalance of nonspecific proteinases and their inhibitors was characterized by activation of proteases associated with depletion of the inhibitory potential while at the systemic level, the increase in proteolytic activity was associated with a reactive increase in levels of inhibitors, which confirms the advisability of local therapy for burns with proteinase inhibitors. The most effective experimental therapy for the proteinase and inhibitor homeostasis disorders was the combined use of applications with a solution of nanosilver and aprotinin.


2021 ◽  
Vol 42 (Supplement_1) ◽  
pp. S191-S192
Author(s):  
Angela R Jockheck-Clark ◽  
Randolph Stone ◽  
Michelle Holik ◽  
Lucy Schaffer ◽  
Shanmugasundaram Natesan ◽  
...  

Abstract Introduction Thermal burns account for 5–10% of casualties sustained in present-day conflicts and are expected to be one of the most common wounds to occur in future conflicts. In prolonged field care (PFC) situations, medical evacuation could be delayed for days. During this time, burn wounds can become infected, detrimentally impact neighboring tissue, and cause systemic immune responses. Therefore, it is essential to test and evaluate non-surgical debridement agents that could be implemented prior to reaching a Role 3 military treatment facility. This work details how the proprietary proteolytic gel SN514 impacts burn debridement when applied within a PFC-like timeline. SN514 contains an enzyme formulation that is thermostable, easy to apply, and selectively degrades non-viable tissue in vitro and in vivo. Methods Deep-partial thickness contact burns were created using an established porcine model and covered with gauze or an antimicrobial incise drape. Four days later, the burns were treated with one of five treatments: 0.2% SN514, 0.8% SN514, a vehicle control, gauze, or an antimicrobial silver dressing. Treatments were re-applied every 24 hours for 72 to 96 hours. The effects of the treatment regiments were compared histologically. Biopsies were also taken to monitor bacterial contamination levels. Results Burns treated with SN514 were partially debrided and visually distinct from those treated with gauze, the silver dressing, or the vehicle control. Preliminary analyses suggest that SN514-treated burns that had been covered with “dry” gauze had a much lower debridement efficiency than those treated with the incise drape. This suggests that SN514 debridement efficiency may depend on the presence of a moist eschar. Preliminary analyses also suggest that there was little difference in burn wound bacterial counts among the five treatment groups. Conclusions SN514 is able to debride burns that experienced delayed treatment, without any evidence of harm to the surrounding tissue or evidence of exacerbating the original burn injury. SN514-treated wounds displayed little to no blood loss and did not increase burn wound infection levels compared to wounds treated with gauze or an antimicrobial silver dressing.


2021 ◽  
Vol 42 (Supplement_1) ◽  
pp. S193-S193
Author(s):  
Emre Karakaya ◽  
Aydincan Akdur ◽  
H Ebru ◽  
Ayvazoglu Soy ◽  
Alev Ok Atilgan ◽  
...  

Abstract Introduction Burn is one of the most severe traumas that causes coagulative destruction of the skin. The use of various products that accelerate wound healing in patients with burn may affect the patient’s survival and reduce the complications that may be seen. In the present study we aimed effects of subcutaneous ozone injection on second degree burn wound. Methods A total of 72 Sprague-Dawley male rats included in the study were divided randomly into three groups (control group (CG), silver sulfadiazine group (SG), ozone group (OG)) and each group was divided randomly two subgroups (as sacrificed on d7 and on d14).A deep second degree scald burns were created on the lower back. In CG subcutaneous 0.9% serum saline was injected daily into the burn area. In SG, burns were dressed with silver sulfadiazine daily and in OG subcutaneous ozone was injected daily into the burn area. Tissue hydroxyproline level measurement and histopathological evaluation were done. Results When the groups were compared in terms of weight change, no significant difference was found on the 7th and 14th days. In the evaluation made in terms of tissue hydroxyproline, tissue hydroxyproline level in OG was found to be significantly higher on both the 7th and 14th days (p &lt; 0.001). In histopathological evaluations, it was determined that wound healing in OG was significantly higher than in the other groups. Conclusions According to the results, subcutaneous ozone therapy is more effective than silver sulphadiazine in the healing process of second-degree burn wounds and it can be safely used in the treatment of burn wounds.


Polymers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 3116
Author(s):  
Thien Do ◽  
Tien Nguyen ◽  
Minh Ho ◽  
Nghi Nguyen ◽  
Thai Do ◽  
...  

(1) Background: Wounds with damages to the subcutaneous are difficult to regenerate because of the tissue damages and complications such as bacterial infection. (2) Methods: In this study, we created burn wounds on pigs and investigated the efficacy of three biomaterials: polycaprolactone-gelatin-silver membrane (PCLGelAg) and two commercial burn dressings, Aquacel® Ag and UrgoTulTM silver sulfadiazine. In vitro long-term antibacterial property and in vivo wound healing performance were investigated. Agar diffusion assays were employed to evaluate bacterial inhibition at different time intervals. Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and time-kill assays were used to compare antibacterial strength among samples. Second-degree burn wounds in the pig model were designed to evaluate the efficiency of all dressings in supporting the wound healing process. (3) Results: The results showed that PCLGelAg membrane was the most effective in killing both Gram-positive and Gram-negative bacteria bacteria with the lowest MBC value. All three dressings (PCLGelAg, Aquacel, and UrgoTul) exhibited bactericidal effect during the first 24 h, supported wound healing as well as prevented infection and inflammation. (4) Conclusions: The results suggest that the PCLGelAg membrane is a practical solution for the treatment of severe burn injury and other infection-related skin complications.


2019 ◽  
Vol 9 (6) ◽  
pp. 4586-4590 ◽  

Ceramides are structural components of the stratum corneum that regulate cell proliferation and differentiation. The study of the effect of the cream containing dexpanthenol and ceramide on the proliferation processes and regeneration of burn wounds in rats. Experimental rats with III-A degree thermal burn were treated separately with the following preparations: cream with ceramides, cream with dexpanthenol and ceramides and cream "Bepanten". The proliferative-regenerative activity of the drugs was investigated by studying the content of the Ki-67 producing cells and the content of ribonucleic acid (RNA) in the cytoplasm of the granulation tissue fibroblasts. Ceramides contributed to wounds healing, increasing the content of Ki-67 antigenpositive cells, accelerating the formation of scar in the wound. The therapeutic effect of creams with ceramides exceeds the efficacy of the reference preparation “Bepanten” cream. The addition of ceramides to dexpanthenol increases the quality and reduces the wound healing time.


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