The purpose of this study was to investigate tissue repair of excisional wounds in hyperglycemic animals treated with chitosan-alginate membranes (CAM) produced in the presence of glycerol. 8-week C57B1 male mice were divided into normoglycemic animals with a 0.9% saline solution topical treatment (CTSF); hyperglycemic animals with 0.9% saline solution topical treatment (DMSF) and hyperglycemic animals with glycerol-plasticized chitosan-alginate membrane topical treatment (DMCAM). On post-wound day three, the DMCAM group presented a lower number of leukocytes, mature mastocytes, a higher number of vessels (p < 0.05), and active mastocytes (p < 0.05) when compared to the CTSF and DMSF groups. There were no differences regarding the distribution, deposition, organization, and thickness of collagen fibers. On day 7 there were no differences in the analysis of fibroblasts, mastocytes, and TGF−β1 and VEGF expressions among the groups. Regarding collagen fibers, the DMCAM group presented slight red-orange birefringence when compared to the CTSF and DMSF groups. On day 14 there was a slight concentration of thinner elastic fibers for the DMCAM group, with a greater reorganization of papillary skin and improved red-orange birefringence collagen fibers, as well as net-shaped orientation, similar to intact skin. In addition, improved elastic fiber organization distributed in the entire neo-dermis and a larger presence of elaunin fibers were observed, in a similar pattern found in the intact skin. The use of CAM in cutaneous lesions boosted tissue repair since there was a smaller number of inflammatory cells and mastocytes, and an improvement in collagen deposition and collagen fibers. These results demonstrate the high potential of plasticized chitosan-alginate membrane for skin wound dressing of hyperglycemic patients.

Background: Photobiomodulation consists of inducing healing by irradiating light. This scoping review investigates the effect of blue light on the healing process. Methods: The MEDLINE, Web of Science, Scopus, and CINAHL databases were searched. Two reviewers independently examined the search results and extracted data from the included studies. A descriptive analysis was performed. Results: Twenty-two articles were included. Studies were categorized as in vitro/mixed, preclinical, and clinical. The power density used was 10–680 mW/cm2 in most of the in vitro/preclinical studies, the irradiation time ranged from 5 s to 10 min, and different wavelengths and energy densities were used. In clinical studies, the wavelength ranged from 405 to 470 nm, and the energy density varied from 1.5 to 30 J/cm2. Conclusions: A low energy density (<20 J/cm2) was able to stimulate the different cell types and proteins involved in healing, while a high energy density, 20.6–50 J/cm2, significantly reduced cell proliferation, migration, and metabolism. There is a great variety of device parameters among studies, and this makes it difficult to conclude what the best technical specifications are. Thus, further studies should be performed in order to define the appropriate parameters of light to be used.

Introdução: O reparo tecidual é um processo biológico, complexo e dinâmico e quando associado ao Diabetes Mellitus possui moduladores negativos da sinalização da insulina que desencadeiam atraso na cicatrização das feridas. Estudos mostram que a Insulina tem grande importância na qualidade do tecido cicatricial. Objetivo: Comparar o efeito do tratamento tópico do gel de Insulina com o creme de insulina no processo de cicatrização de camundongos diabéticos. Método: o estudo foi composto por dois grupos: 1º Animais diabéticos com feridas tratadas com creme de insulina; 2º Animais diabéticos com feridas tratadas com gel de insulina. O diabetes foi induzido com estreptozotocina 60mg/Kg por 5 dias, via intraperitoneal. Sob anestesia, a ferida na região dorsal foi feita com molde de 1 cm2, sendo tratadas diariamente e retiradas nos 4°, 8º e 14º dias para posterior análise. O processo de cicatrização foi avaliado macroscopicamente por meio de fotografias nos dias zero, 2, 4, 6, 8, 10, 12 e 14 pós-lesão e microscopicamente quanto à histologia, por hematoxilina & Eosina, e quanto a angiogênese e proliferação celular por imuno-histoquimica. Para análise estatística foi utilizado o teste t de Student, nível de significância foi de p<0,05. Conclusão: Nossos resultados preliminares sugerem que o gel de insulina apresenta melhor efetividade na contração da ferida no oitavo dia pós lesão com menor infiltrado inflamatório quando comparado ao creme com insulina.