Acceleration of cutaneous wound healing by Lucilia sericata maggots in diabetic Wistar rats

@#The study was aimed to evaluate the effectiveness of maggot therapy in healing of cutaneous infected wound in streptozotocin (STZ) induced diabetic Wistar rat. For live maggots, the sterilized eggs of Lucilia sericata were obtained from colonies established in laboratory. Diabetes model was established in 48 male Wister rat by intra-peritoneal injection of STZ at the dose of 60 mg/kg body-weight. Cutaneous wounds exposed with mixed colonies of bacteria like Staphylococcus aureus, E. coli and Pseudomonas aeruginosa were prepared in all rat. The animals equally divided in 4 groups with 12 rats each being presented as treatment group of control, antibiotic, maggot and maggot with antibiotic in combination. All treatments were done once and hold for 24 hours. Wound kinetics and bacterial bio burden were measured at weekly interval to till complete healing. Significant reduction in wound area with maximum contraction was found (>95%) in maggot treated group when compared to antibiotic treated (79%) and control (72%). In maggot as well as maggot and antibiotic in combination group showed early elimination of bacterial bio-burden 7.88±0.03log CFU/ml to 1.12±0.65log CFU/ml and 7.86±0.04) log CFU/ml to 1.54±0.52log CFU/ml respectively in three weeks of time. Early healing indication was also experienced on histomorphological examination of wounded tissue of maggot treated groups by early and better epithelialization, collagenation and neovascularization with complete healing of wound in three weeks in comparison to antibiotic and control respectively. However, the present study did not show any difference in healing of wound with use of maggot alone or in antibiotic combination. Live maggot of Lucilia sericata effectively lower bacterial bioburden and and accelerate healing of infected cutaneous wound in diabetic conditions.

A utilização de coberturas oclusivas: a influência sobre a cicatrização de feridas excisionais em camundongos / The use of occlusive coverages: the influence on the healing of excisional wounds in mice

INTRODUÇÃO: O cuidado do paciente com feridas é um constante desafio na prática clínica do enfermeiro. As coberturas oclusivas e não oclusivas são utilizadas no tratamento de feridas e existe uma lacuna de conhecimento sobre a influência dessas indicações no processo de cicatrização. OBJETIVO: O objetivo do presente estudo foi avaliar a influência de coberturas oclusivas sobre a cicatrização de feridas cutâneas excisionais em camundongos C57BL/6. MATERIAIS E MÉTODOS: Trata-se de um estudo translacional pré-clínico, comparativo e controlado. Os camundongos foram divididos em três grupos experimentais e o tratamento das feridas excisionais deles foram classificados como: animais que receberam oclusão com hidrocolóide (HD), animais que receberam oclusão com filme transparente de poliuretano (FT) e animais sem oclusão (SO). Os grupos foram avaliados quanto: a taxa de fechamento das feridas, o infiltrado de neutrófilos e macrófagos, dosagem da citocina TNF-α, o fator de crescimento angiogênico VEGF, a expressão protéica de HIF-1α e, histologicamente, o desenvolvimento de novos vasos sanguíneos. As cicatrizes das feridas foram analisadas por juízes independentes quanto à apresentação estética no décimo quarto dia de segmento. RESULTADO: No terceiro dia do processo de cicatrização, foi possível observar, macroscopicamente, que o fechamento das feridas cutâneas excisionais foi acelerado nos animais cuja ferida foi ocluída, utilizando-se tanto filme transparente quanto o hidrocolóide. Ainda no período de três dias, observou-se diminuição nos níveis da citocina pró-inflamatória TNF-α nas feridas ocluídas com hidrocolóide quando comparada com os grupos SO e FT. O acúmulo de neutrófilos também diminuiu, significativamente, ao terceiro dia de cicatrização no grupo tratado com hidrocolóide, quando comparado aos grupos SO e FT, respectivamente. O conteúdo dos macrófagos apresentou níveis significativamente mais altos ao terceiro dia no grupo FT quando comparado a SO. Ao sexto dia de estudo, evidenciaram-se dosagens significativamente aumentadas de macrófagos no grupo HD, contrastando com os grupos SO e FT. Os níveis de VEGF apresentaramse expressivamente aumentados ao sexto dia de cicatrização, nos animais cujas feridas estavam ocluídas com filme transparente de poliuretano e hidrocolóide. Houve aumento dos níveis do fator indutor de hipóxia 1-alfa nos animais submetidos a oclusão quando comparados aos sem oclusão. A análise qualitativa do reparo em cicatriz das feridas permitiu afirmar que houve concordância moderada e significativa entre os juízes no grupo HD e concordância substancial e significativa nas cicatrizes dos animais SO. CONSIDERAÇÕES FINAIS: Considerando-se que a resposta inflamatória é um processo imunológico fundamental para o processo de reparo de feridas, quando ocorre de forma controlada, sugere-se que a oclusão modula a resposta inflamatória. Tal achado é evidenciado por meio da inibição parcial da citocina pró-inflamatória TNF- α, da redução de acúmulo de neutrófilos e dos níveis mais altos de macrófagos. A oclusão das feridas não evidenciou aumento quantitativo de capilares em relação ao grupo sem oclusão.(AU)

INTRODUCTION: The care of the wounded patient is a constant challenge in the nurse's clinical practice. Occlusive and non-occlusive coverages are used to treat wounds and there is a lack of knowledge about the impact of these indications on the healing process. OBJECTIVE: The objective of the present study was to evaluate the influence of occlusive coatings on the cicatrization of cutaneous excisional wounds in C57BL / 6 mice. MATERIALS AND METHODS: It is a pre-clinical, comparative and controlled translational study. The mice were divided into three experimental groups and the treatment of excisional wounds of these were classified as: animals that received occlusion with hydrocolloid (HD), animals that received occlusion with transparent polyurethane film (FT) and animals without occlusion (SO). The groups were evaluated for: wound closure rate, neutrophil and macrophage infiltration, TNF-α cytokine dosing, VEGF angiogenic growth factor, HIF-1α protein expression and, histologically, the development of new blood vessels. Wound scars were analyzed by independent judges regarding the aesthetic presentation on the fourteenth day of the segment. RESULTS: On the third day of the healing process it was possible to observe, macroscopically, that the closure of excisional skin wounds was accelerated in animals whose wound was occluded using both transparent and hydrocolloid films. Also, in the three-day period, there was a decrease in TNF-α proinflammatory cytokine levels in the hydrocolloid occluded wounds when compared to the SO and FT groups. Neutrophil accumulation also significantly decreased on the third day of healing in the group treated with hydrocolloid occlusion when compared to the SO and FT groups, respectively. Macrophage content had significantly higher levels, on day 3, in the FT group, when compared to OS. On the sixth day of the study, significantly increased dosages of macrophages were detected in the HD group, contrasting with the SO and FT groups. VEGF levels were expressively increased on the sixth day of healing in animals whose wound was occluded with transparent polyurethane film and hydrocolloid film. There was an increase in levels of the factor inducing 1-alpha hypoxia in the animals submitted to occlusion when compared to those without occlusion. The qualitative analysis of the wound healing repair allowed to affirm that there was moderate and significant agreement, between the judges, in the HD group and substantial and significant concordance in the scars of the SO animals. FINAL CONSIDERATIONS: Considering that the inflammatory response is a fundamental immunological process for the wound repair process, when it occurs in a controlled way, it is suggested that the occlusion modulates the inflammatory response. Such a finding is evidenced by partial inhibition of the proinflammatory cytokine TNF-α, reduction of neutrophil accumulation, and higher levels of macrophages. The wounds occlusion did not show a quantitative increase of capillary vessels in relation to the group without occlusion.(AU)

Células-tronco mesenquimais aplicadas nas fases inflamatória e proliferativa da cicatrização de feridas cutâneas / Mesenchymal stem cells applied to the inflammatory and proliferative phases of wound healing

A cicatrização de feridas é um processo que requer a interação de várias células da derme e epiderme. O objetivo deste trabalho foi avaliar qual o momento da aplicação das células das ADSCs em feridas cutâneas agudas que faria diferença na cicatrização nos primeiros sete dias da lesão. As células-tronco foram isoladas do tecido adiposo de camundongos C57Bl/6 GFP+. Para tanto, foram utilizados 49 camundongos C57Bl/6, divididos em quatro grupos: grupo I (GI/controle; n=14); grupo II (GII; n=14): ADSCs injetadas no d0; grupo III (GIII; n=14): ADSCs injetadas no terceiro dia; e Grupo IV (GIV; n=7): ADSCs injetadas no quinto dia. As avaliações clínicas ocorreram nos dias zero, três, cinco e sete, e as histopatológicas nos dias cinco e sete. Na metodologia proposta, foi observado que o uso de ADSCs aumenta a vascularização, a formação de tecido de granulação, a colagenização e incrementa o número de folículos pilosos em apenas sete dias de avaliação. Além disso, o momento da aplicação das células não repercutiu diferenças significativas nas fases inflamatória e proliferativa do processo de cicatrização das feridas cutâneas.(AU)

Wound healing is a process that requires the interaction of various cells in the dermis and epidermis. The aim of this study was to evaluate the action of ADSCs in the treatment of acute wounds in order to understand if application time of the cells results in a difference in healing the first seven days of injury. The stem cells were isolated from adipose tissue of C57BL / 6 mice GFP +. Thus, we used 49 mice C57BL / 6 divided into four groups: Group I (GI / control, n=14); Group II (GII; n=14): ADSCs injected to the d0; Group III (GIII; n=14): ADSCs injected on the 3rd day, and Group IV (GIV; n=7): ADSCs injected day 5(d5). Clinical evaluations were performed on days 0, 3, 5 and 7 and the histopathology on days 5 and 7. In the proposed methodology, the use of ADSCs increased vascularization, formation of granulation tissue, collagen deposition and increases the number of hair follicles in just seven days of evaluation. In addition, the time of application of the cells did not affect significant differences in the inflammatory and the proliferative phase of wound healing skin.(AU)

Effect of autologous platelet-rich plasma application on cutaneous wound healing in dogs

This study was conducted to identify the effectiveness of platelet-rich plasma (PRP) and efficacy of intralesional injection as a method of application to acute cutaneous wounds in dogs. Healthy adult beagles (n = 3) were used in this study. Autologous PRP was separated from anticoagulant treated whole blood in three dogs. Cutaneous wounds were created and then treated by intralesional injection of PRP in the experimental group, while they were treated with saline in the control group on days 0, 2 and 4. The healing process was evaluated by gross examination throughout the experimental period and histologic examination on day 7, 14 and 21. In PRP treated wounds, the mean diameter was smaller and the wound closure rate was higher than in the control. Histological study revealed that PRP treated wounds showed more granulation formation and angiogenesis on day 7, and faster epithelialization, more granulation formation and collagen deposition were observed on day 14 than in control wounds. On day 21, collagen deposition and epithelialization were enhanced in PRP treated groups. Overall, PRP application showed beneficial effects in wound healing, and intralesional injection was useful for application of PRP and could be a good therapeutic option for wound management in dogs.

Production of vegetable oil blends and structured lipids and their effect on wound healing / Produção de misturas de óleos vegetais e lípidos estruturados e o seu efeito na cicatrização de feridas

Two oil blends (sunflower/canola oils 85/15 (BL1) and canola/linseed oils 70/30 (BL2)), were prepared and enzymatically interesterified to be applied to surgically-induced wounds in rats. Following surgery, the animals were submitted to the Treatment with Physiological Saline (TPS) (control group), Blends (TBL), and Structured Lipids (TSL). The control group (TPS) received physiological saline solution for 15 days. In TBL, BL1 was administered during the inflammation phase (days 0-3) and BL2 in the tissue formation and remodeling phase (days 4-15). In TSL, Structured Lipid 1 (SL1) and Structured Lipid 2 (SL2) were used instead of BL1 and BL2, respectively. The aim of this study was to compare wound closure evolution among rats treated with the blends or structured lipids versus control rats treated with physiological saline. The wound healing process was evaluated by measuring the wound areas along the treatments and the concentrations of cytokines. An increase in the areas of wounds treated with the blends and structured lipids in the inflammatory phase was observed, followed by a steeper closure curve compared to wounds treated with physiological saline. The changes observed during the inflammatory phase suggest a potential therapeutic application in cutaneous wound healing which should be further investigated...

Duas misturas de óleos vegetais (girassol/canola 85/15 (BL1) e canola/linhaça, 70/30 (BL2) foram preparadas e interesterificadas por via enzimática para serem aplicadas em feridas induzidas cirurgicamente em ratos. Após a cirurgia, os animais foram submetidos ao tratamento com soro fisiológico (TPS) (grupo controle), tratamento com as misturas (TBL) e tratamento com os lipídios estruturados (TSL). O grupo controle (TPS) recebeu soro fisiológico por 15 dias. Em TBL, BL1 foi administrada durante a fase de inflamação (dias 0-3) e BL2 na fase de formação de tecido e remodelação (dias 4-15). Em TSL, os lipídios estruturados SL1 e SL2 foram usados em vez de BL1 e BL2, respectivamente. O objetivo deste estudo foi avaliar a evolução do fechamento das feridas dos grupos de ratos tratados com as misturas ou lipídios estruturados em comparação com os ratos do grupo controle, tratados com soro fisiológico. O processo de cicatrização das feridas foi avaliado através da medição das áreas das feridas ao longo dos tratamentos e pela determinação das concentrações de citocinas. Observou-se aumento das áreas das feridas tratadas com as misturas e os lipídios estruturados na fase inflamatória, seguida por um fechamento acentuado de feridas comparado com o tratamento com solução salina. As mudanças observadas durante a fase inflamatória sugerem uma potencial aplicação terapêutica na cicatrização de feridas cutâneas, fazendo-se necessárias investigações posteriores...

Efeitos de uma dieta hiperlipídica e de uma droga anti-inflamatória não-esteróide inibidora seletiva da ciclooxigenase-2 sobre a cicatrização cutânea de ratos Wistar propensos e resistentes a obesidade / Effects of a high fat diet and an anti-inflammatory drug non steroidal inhibitor selective of cyclooxygenase-2 on the cutaneous wound healing Wistar rats likely resistant to obesity

O sobrepeso induzido por uma dieta rica em gordura atrasa a cicatrização através do prolongamento da fase inflamatória, entretanto, quando recebem uma dieta obesogênica, alguns ratos são suscetíveis a desenvolver sobrepeso, enquanto outros são resistentes. Drogas anti-inflamatórias não-esteróides são frequentemente utilizadas para reduzir a inflamação. Este estudo investigou a cicatrização cutânea em ratos propensos a obesidade induzida por dieta (DIO) e em ratos resistentes a dieta (DR) e avaliou a participação da administração do celecoxibe na cicatrização cutânea destes animais. Ratos machos foram alimentados com uma dieta padrão (Controle, C) ou com uma dieta rica em gordura saturada (30%). Após 19 semanas, o grupo experimental foi subdividido nos grupos DIO e DR. Uma lesão excisional foi feita e os animais foram mortos 7 ou 14 dias depois. Os grupos tratados receberam uma dose diária de 5 ou 10 mg/kg/dia de celecoxibe a partir de dois dias antes da lesão até 7 dias após a lesão, quando foram mortos. O peso corporal foi maior no grupo DIO comparado aos grupos C e DR. A gordura retroperitoneal foi maior no grupo DIO do que nos grupos C e DR e foi maior no grupo DR do que no grupo C. O tratamento com o celecoxibe não alterou o maior peso corporal apresentado pelo grupo DIO ou a maior porcentagem de gordura retroperitoneal apresentada pelos grupos DIO e DR. Todos os grupos tratados com celecoxibe 10 mg apresentaram atraso na cicatrização e não foram mais analisados. O grupo DIO apresentou intolerância a glicose, e ambos os grupos DIO e DR apresentaram atraso na contração e na reepitelização da lesão. O tratamento com celecoxibe 5 mg reverteu a intolerância a glicose no grupo DIO e a contração atrasada nos grupos DIO e DR. Comparado ao grupo DR, o grupo DIO apresentou maior quantidade de células inflamatórias, assim como maiores níveis de peroxidação lipídica. O tratamento com celecoxib (5 mg) não reduziu o número de PMN, mas reduziu o número de mastócitos...

Overweight induced by high-fat diet delays wound healing through elongation of inflammatory phase, however, when receiving on obesogenic diet, some rats are susceptible to developing the overweight phenotype, whereas others are resistant. Nonsteroidal anti-inflammatory drugs are frequently used to reduce the inflammation. This study investigated cutaneous wound healing in diet-induced obesity (DIO)-prone and diet-resistant (DR) rats and evaluated the contribution of celecoxib administration on cutaneous wound healing of these animals. Male rats were fed with a standard (Control, C) or high-saturated fat (30%) diet. After 19 weeks, experimental group was subdivided into DIO and DR groups. An excisional lesion was made and the animals were killed 7 or 14 days later. Treated groups received a daily dose of celecoxib 5 or 10 mg/kg/day from two days before wounding until 7 days after wounding when were killer. The body weight was higher in the DIO group compared to the C and DR groups. Retroperitoneal fat was higher in the DIO group than in the C and DR groups and was higher in the DR group than in the C group. Celecoxib-treatment did not alter the higher body weight presented by DIO group of higher retroperitoneal fat percentage displayed by DIO and DR groups. All groups treated with celecoxib 10 mg showed delayed wound healing, and weren't further analysed. The DIO group presented glucose intolerance, and both the DIO and DR groups presented delayed wound contraction and re-epithelialisation. The celecoxib 5 mg-treatment reversed the glucose intolerance in the DIO group and the delayed contraction in the DIO and DR groups. Compared to the DR group, the DIO group displayed higher amounts of inflammatory cells as well as higher levels of lipid peroxidation. Celecoxib-treatment (5 mg) did not reduce the number of PMN, but reduce mast cells number in DIO group and macrophages number and lipid peroxidation in both groups. Myofibroblastic differentiation...

Effect of gallium-arsenide laser, gallium-aluminum-arsenide laser and healing ointment on cutaneous wound healing in Wistar rats

This study determined the effects of gallium-aluminum-arsenide laser (GaAlAs), gallium-arsenide laser (GaAs) and Dersani® healing ointment on skin wounds in Wistar rats. The parameters analyzed were: type I and III collagen fiber concentrations as well as the rate of wound closure. Five wounds, 12 mm in diameter, were made on the animals’ backs. The depth of the surgical incision was controlled by removing the epithelial tissue until the dorsal muscular fascia was exposed. The animals were anesthetized with ketamine and xylazine via intraperitoneal injection. The rats were randomly divided into five groups of 6 animals each, according to the treatment received. Group 1 (L4): GaAs laser (4 J/cm²); group 2 (L30): GaAlAs laser (30 J/cm²); group 3 (L60): GaAlAs laser (60 J/cm²); group 4 (D): Dersani® ointment; group 5 (control): 0.9 percent saline. The applications were made daily over a period of 20 days. Tissue fragments were stained with picrosirius to distinguish type I collagen from type III collagen. The collagen fibers were photo-documented and analyzed using the Quantum software based on the primary color spectrum (red, yellow and blue). Significant results for wound closing rate were obtained for group 1 (L4), 7.37 mm/day. The highest concentration of type III collagen fibers was observed in group 2 (L30; 37.80 ± 7.10 percent), which differed from control (29.86 ± 5.15 percent) on the 20th day of treatment. The type I collagen fibers of group 1 (L4; 2.67 ± 2.23 percent) and group 2 (L30; 2.87 ± 2.40 percent) differed significantly from control (1.77 ± 2.97 percent) on the 20th day of the experiment.

COMP-angiopoietin 1 Gene Transfer Enhances Cutaneous Wound Healing by Promoting Angiogenesis

BACKGROUND: Angiogenesis is crucial for wound healing and exogenous supplements of the angiogenic growth factors have been known to promote cutaneous wound healing. Angiopoietin (Ang) 1 is a recently discovered angiogenic factor and there have been few studies of its effect on cutaneous wound healing. OBJECTIVE: We examined the effect of Ang 1 on cutaneous wound healing. METHODS: Cartilage oligomeric matrix protein (COMP)-Ang 1 (Ade-COMP-Ang 1)- was intravenously injected to rats two days before surgery creating full-thickness wounds. The clinical wound healing rate and the number of vessels in the skin samples were evaluated on days 3, 7 and 14 post operation. RESULTS: At post-operation day 3, 7 and 14, the clinical wound healing rate was 38.3%, 59.4% and 92.1%, respectively, in the Ade-COMP-Ang 1-treated group, compared with 20.5%, 47.5% and 87.3%, respectively, in the Ade-LacZ-treated group. There were significant differences in the results of day 3 and day 7 between two groups (p<0.05). Histopathologically, the number of the vessels of the Ade-COMP-Ang 1-treated group was 73.7, 94.1 and 62.7 at day 3, 7 and 14, compared with that of the Ade-LacZ-treated group, 53.5, 83.9, and 56.9. The differences in the results of the two groups were statistically significant (p<0.05). CONCLUSION: These results indicate that Ade-COMP-Ang 1 therapy significantly accelerats wound healing by promoting angiogenesis. However, further study using Ade-COMP-Ang 1 gene therapy for chronic wounds in which the formation of new blood vessels is impaired is needed in the near future.

Cotton gauze bandage: a support for protease immobilization for use in biomedical applications

The covalent immobilization of trypsin on sterilized cotton gauze bandage was carried out for future use as an anti-inflammatory agent on wound dressing. The optimal immobilization conditions were determined: the influence of pH, concentration, and volume of the trypsin solution used in the immobilization procedure was studied. The catalytic properties and kinetic parameters, as well as the storage stability of the immobilized and free enzyme were compared. Results showed that the optimal pH and temperature for the immobilized trypsin in the hydrolysis of N-benzoyl-DL-arginine p-nitroanilide were 9.5 and 55 ºC, which were higher than those of the free form (7.5 and 45 ºC). It was found, at 37 ºC and pH 7.0 (approximately, the physiological conditions), that the Km (Michaelis constant) was 3.98 µmol/mL and that Vmax (maximal reaction rate) was 0.719 µmol/(min mg) for the immobilized trypsin, compared to a Km of 2.46 mmol/mL and a Vmax of 2.89 µmol/(min mg) for the free trypsin. The amount of immobilized trypsin was 6 mg/g dried support. After 30 days, no trypsin had liberated from the support. The superior performance of the immobilized trypsin demonstrates its potential application in practice.

Neste trabalho foi efetuada a imobilização de tripsina numa gaze esterilizada de algodão. Foram determinadas as condições ótimas de imobilização: foi estudada a influência do pH, concentração e volume da solução de tripsina usada na imobilização na hidrólise da N-benzoil-DL-arginina p-nitroanilida. As propriedades catalíticas, os parâmetros cinéticos e as condições de estabilidade das enzimas livre e imobilizada foram comparadas. Os resultados mostraram que o pH e a temperatura ótimos para a tripsina imobilizada foram 9.5 e 55 ºC, respectivamente, maiores que os correspondentes da forma livre (7,5 e 45 ºC). A 37 ºC e a pH 7,0 (aproximadamente as condições fisiológicas) Km (constante de Michaelis) foi 3,98 µmol/mL e Vmax (velocidade máxima de reacção) foi 0,719 µmol/(min mg) para a tripsina imobilizada; para a tripsina livre os valores correspondentes foram 2,46 µmol/mL e 2,89 µmol/(min mg). A quantidade de enzima imobilizada foi de 6 mg/g (base seca). Após 30 dias não se verificou libertação de tripsina do suporte. O bom desempenho da tripsina imobilizada na gaze esterilizada de algodão comprova a sua potencial utilização como agente anti-inflamatório no tratamento de lesões cutâneas.