Effects of Different Protocols of Low-Level Laser Therapy on Collagen Deposition in Wound Healing.

The low-level laser has proven successful in stimulating the production of collagen in wound healing assays. However, diversity has been observed in the protocols used. This work has evaluated the effects of three protocols of low-level laser therapy (LLLT) in the healing of open wounds in rats. Standard-sized wounds of 1 cm2 were performed with a scalpel in the middorsal region of 60 male Wistar rats weighing 225±25 g, and they were assigned into four groups (n=15): CTR (non-irradiated animals), LT1 (20 J/cm2 daily), LT2 (16 J/cm2 daily) and LT3 (20 J/cm2 daily). After 7, 14 and 21 days, five animals/day were euthanized and the wounds analyzed histologically. Data were subjected to normality analysis of distribution using Shapiro-Wilk test. Gaussian data were analyzed using ANOVA and Bonferroni tests whereas non-Gaussian data were analyzed using Kruskal-Wallis and Dunn tests, considering significant p values less than 0.05. The LLLT in all protocols reduced the inflammation and collagen deposition increased significantly (p<0.05). However, LT2 showed the highest levels of collagen in all phases of the study (p<0.05) induced faster replacement of immature collagen III by mature collagen I in the early stages of repair and early collagen remodeling promoted by providing better organization architectural beams deposited. It was concluded that all protocols induced an increase in collagen scar. However, the protocol 2 (16 J /cm2, daily application) promoted the most significant increases in collagen deposition, accelerated maturation of collagen and showed the best architecture of the final fibrous scarring.

Effects of different protocols of low-level laser therapy on collagen deposition in wound healing

Abstract The low-level laser has proven successful in stimulating the production of collagen in wound healing assays. However, diversity has been observed in the protocols used. This work has evaluated the effects of three protocols of low-level laser therapy (LLLT) in the healing of open wounds in rats. Standard-sized wounds of 1 cm2 were performed with a scalpel in the middorsal region of 60 male Wistar rats weighing 225±25 g, and they were assigned into four groups (n=15): CTR (non-irradiated animals), LT1 (20 J/cm2 daily), LT2 (16 J/cm2 daily) and LT3 (20 J/cm2 daily). After 7, 14 and 21 days, five animals/day were euthanized and the wounds analyzed histologically. Data were subjected to normality analysis of distribution using Shapiro-Wilk test. Gaussian data were analyzed using ANOVA and Bonferroni tests whereas non-Gaussian data were analyzed using Kruskal-Wallis and Dunn tests, considering significant p values less than 0.05. The LLLT in all protocols reduced the inflammation and collagen deposition increased significantly (p<0.05). However, LT2 showed the highest levels of collagen in all phases of the study (p<0.05) induced faster replacement of immature collagen III by mature collagen I in the early stages of repair and early collagen remodeling promoted by providing better organization architectural beams deposited. It was concluded that all protocols induced an increase in collagen scar. However, the protocol 2 (16 J /cm2, daily application) promoted the most significant increases in collagen deposition, accelerated maturation of collagen and showed the best architecture of the final fibrous scarring.

Resumo O laser de baixa potência provou ter sucesso em estimular a produção de colágeno em ensaios de cicatrização de feridas. Entretanto, grande diversidade tem sido observada nos protocolos utilizados. Este trabalho avaliou os efeitos de três protocolos de Terapia a Laser de Baixa Potência (TLBP) na cicatrização de feridas abertas em ratos. Feridas padronizadas com 1 cm2 de tamanho foram realizadas com um bisturi na região do dorso de 60 ratos Wistar machos pesando 225±25g, e foram divididos em quatro grupos (n=15): CTR (animais não irradiados), LT1 (20 J/cm2 diariamente), LT2 (16 J/cm2 diariamente) e LT3 (20 J/cm2 diariamente). Após 7, 14 e 21 dias, cinco animais/dia foram eutanasiados e as feridas analisadas histologicamente. Os dados foram submetidos à análise de normalidade da distribuição pelo teste de Shapiro-Wilk. Os dados gaussianos foram analisados pelos testes ANOVA e Bonferroni, enquanto que os dados não Gaussianos foram analisados pelos testes de Kruskal-Wallis e Dunn, considerando-se valores p significativos menores que 0,05. A TLBP em todos os protocolos reduziu a inflamação e aumentou significativamente a deposição de colágeno (p<0,05). Entretanto, LT2 apresentou os maiores níveis de colágeno em todas as fases do estudo (p<0,05), induzindo a substituição mais rápida do colágeno imaturo III pelo colágeno maduro I nos estágios iniciais de reparo e remodelação precoce do colágeno promovida por melhor organização dos feixes depositados. Concluiu-se que todos os protocolos induziram aumento da cicatriz de colágeno. Entretanto, o protocolo 2 (16 J/cm2, aplicação diária) promoveu os aumentos mais significativos na deposição de colágeno, acelerou a maturação do colágeno e apresentou a melhor arquitetura da cicatriz fibrosa final.

Effects of the essential oil of Alpinia zerumbet (Pers.) B.L. Burtt & R.M. Sm. on healing and tissue repair after partial Achilles tenotomy in rats

Abstract Purpose: To investigate the cellular response to injury, analyzing histopathologic changes associated with increased cellularity, degeneration and disorganization of collagen fibers. Methods: Thirty wistar rats were divided in two groups after partial Achilles tenotomy: the right hind paw were treated with the essential oil of Alpinia zerumbet (EOAz), diluted to 33% (0.3 mL kg-1), and the left hind paw received sunflower oil for 3, 14, 30 and 90 days. Statistical significance was determined using a Chi-square and Pearson Correlation qualitative variables test. Moreover, Mann-Whitney U-test test for comparison between different groups of the same cell, one-way ANOVA, and Tukey's test of quantitative measurement. Results: A decrease hyperemia (p < 0.001) was observed in the acute phase of inflammatory cell number (p < 0.001), whereas sub-acute phase was marked by significant correlation with macrophages in fibroblasts (r = 0.17, p = 0.03), with probable induction a dense and modeled tissue. At chronic phase, it was found an increase in the number of fibroblasts and a higher percentage of type I collagen fibers (78%) compared with control collagen fibers (55%). Conclusion: Oil of Alpinia zerumbet stimulated the process of maturation, organization and tissue repair which gave it greater resistance.

UVA-UVB photoprotective activity of topical formulations containing Morinda citrifolia extract.

Exposure to solar radiation, particularly its ultraviolet (UV) component, has a variety of harmful effects on human health. Some of these effects include sunburn cell formations, basal and squamous cell cancers, melanoma, cataracts, photoaging of the skin, and immune suppression. The beneficial photoprotective effects of topical formulations with the extract, Morinda citrifolia, have not been investigated. This present study aims to investigate the potential benefits of M. citrifolia topical application on the dorsal skin of mice, exposed to UVA-UVB light. Using 7 days of treatment, [before (baseline values) and 20 h after UV exposure], the thickness, skin barrier damage (TEWL), erythema, and histological alterations were evaluated. The results showed that the formulations containing the extract protected the skin against UV-induced damage.

Assessment of antimicrobial activity and healing potential of mucous secretion of Achatina fulica / Evaluación de la actividad antimicrobiana y la cicatrización potencial de la secreción mucosa de Achatina fulica

Achatina fulica's secretion has been recently related to antibacterial, antifungal, and cicatricial properties, and it is influenced by the kind of food offered. Therefore, this study investigated the healing potential of dressing films based on mucous secretion of Achatina fulica. Thus, surgical wounds performed in black wistar rats were dressed with films based on collagen, and on mucous secretion of A. fulica fed with Lactuca sativa; undresses worked as wounds control. After 3, 7, 14 and 21 days the animals were euthanized, and the wounds were microscopically evaluated. On the 3rd and 7th days dressing films based on mucus provided acceleration of the formation maturation of granulation tissue, better epithelization rates, and more rapid replacement of type III for type I collagen fibers. On the 14th and 21st days, these dressings induced more intense deposition and better architectural disposition of type I collagen fibers, and hastened the regeneration of cutaneous phaneros. Dressings obtained from A. fulica fed with Lactuca sativa provided the most expressive results. This study suggests that films produced with mucous secretion of A. fulica can be successfully employed as wound dressing, particularly if snails are fed with Lactuca sativa.

A la secreción mucoproteica del Achatina fulica se le han asignado propiedades antibacterianas, antifúngicas y cicatriciales que pueden estar influidas por el tipo de alimento que se ofrece a este especimen. Este estudio investigó el potencial curativo de películas basadas en la secreción mucosa de Achatina fulica alimentaba con diferentes tipos de plantas. Fueron tratadas heridas provocadas en el dorso de ratas Wistar con películas de colágeno y películas realizadas a partir de la secreción mucosa de A. fulica, alimentados con plantas de lechuga (L. sativa), utilizando como parámetro de comparación la curación del grupo de control. Después de 3, 7, 14 y 21 días los animales fueron sacrificados y las heridas fueron evaluadas microscópicamente. En los días 3 y 7, las heridas tratadas con moco mostraron mejores tasas de formación y maduración del tejido de granulación, epitelización, y más rápido recambio de colágeno tipos III y I. A los días 14 y 21, hubo una intensa deposición del colágeno tipo I y aceleración en la regeneración de la piel. Los resultados obtenidos a partir de A. fulica alimentados con plantas de lechuga (L. sativa) mostraron mejores resultados. Este estudio sugiere que las películas producidas con secreción mucosa de A. fulica pueden ser utilizadas con éxito como apósito, especialmente si los caracoles se alimentan con plantas de lechuga L. sativa.