Banca de DEFESA: RAFAELA DE MELO BARRETO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : RAFAELA DE MELO BARRETO
DATE: 24/02/2022
TIME: 08:30
LOCAL: VÍDEO CONFERÊNCIA
TITLE:

EFFECTS OF THE APPLICATION OF PEPTAN ® HETEROLOGOUS COLLAGEN SCAFFOLDS (PIG AND BOVINE) ON THE REPAIR OF SKIN LESIONS IN MICE

KEY WORDS:

SCAFFOLD, TOLERANCE, COLLAGEN, HEALING, WOUND REPAIR.

PAGES: 20
BIG AREA: Ciências Biológicas
AREA: Morfologia
SUBÁREA: Histologia
SUMMARY:

The skin is constantly exposed to stimuli from the external environment that can cause some injury and interfere with its barrier function. Therefore, mechanisms guarantee wound repair, but some cases can lead to pathological scars that involve, among other factors, impaired function and esthetics. As a result, numerous therapies are being developed to improve healing. Collagen is a biomaterial with potential to be used because it is abundant, biocompatible, biodegradable and capable of helping cell migration and proliferation, in addition to improving matrix deposition. Collagen may also be able to influence the immune response through inhibitory receptors and the indirect effects of tolerance that influence the inflammatory phase of skin lesion repair. Therefore, the aim of this study was to verify the topical application of a heterologous collagen scaffold (PEPTAN®) on the wound on the day the injury is performed and its influence on inflammation and extracellular matrix deposition during the wound closure process in the Swiss mouse skin. The experimental model consisted of performing two excisional lesions and one incisional lesion on the back skin, under anesthesia. Then, the treatment with the dressing was carried out according to the experimental group: Control Saline; PEPTAN 1[1], PEPTAN 1[2], PEPTAN 2[1] and PEPTAN 2[2]. PEPTAN® collagens are differentiated according to the heterologous source, porcine or bovine, and two different molecular masses. The dressings remained for 5 days. The animals were euthanized 7 and 60 days after the injury and the healing was analyzed macro and microscopically after staining with H&E, Toluidine Blue and Gomori's Trichromatic. In incisional lesions, macroscopically at 7d, the PEPTAN 1[1] group presented an aesthetically better lesion, reduction of fibroblasts in the PEPTAN 2[1] and PEPTAN 2[2] groups, reduction of mast cells in the PEPTAN 1[2] group when compared with the PEPTAN 2[1] and At 60d group, the incisional lesions of the PEPTAN 1[1] and PEPTAN 1[2] groups have lighter and aesthetically better scars when compared to saline. Histomorphometric analyzes demonstrate that the PEPTAN 2[2] group presented a greater deposition when compared to the saline group. In excisional lesions, at 7d, the PEPTAN 1[2] group had a smaller area, while the PEPTAN 1[1] group had a larger area. Microscopically, the quantitative analysis showed no statistical difference in the leukocyte and mast cell count. It was observed that the PEPTAN 2[1] group had a greater number of fibroblasts, when compared to the PEPTAN 1[2] and PEPTAN 2[2] groups. At 60d, the PEPTAN 1[1] and PEPTAN 1[2] groups showed better collagen deposition when compared to the Saline group. The saline group presented a more marked and noticeable transition area between the lesion and the adjacent dermis. While the PEPTAN 1[1] and PEPTAN 1[2] groups presented this smoother transition. We conclude that the application of a dressing containing PEPTAN® heterologous collagen scaffold improves the healing of skin lesions, with a better remodeling of the extracellular matrix.

BANKING MEMBERS:
Externa à Instituição - TATIANA CARLA TOMIOSSO - UFU
Interna - 2279745 - ERIKA LORENA FONSECA COSTA DE ALVARENGA
Externo à Instituição - MARCOS AUGUSTO DE SÁ - UFMG
Interna - 2144084 - PRISCILA TOTARELLI MONTEFORTE
Presidente - 2104326 - RAQUEL ALVES COSTA
Externo à Instituição - THIAGO CANTARUTI ANSELMO