Physical and biological properties of the new biological dressing constituted of Rana catesbeiana skin

OLIVEIRA, C. R.(1), VIEIRA, C.M.(1), ARAÚJO, A.C.M.(1), ADORNO, J.(5), CUNHA FILHO, G.A.(1), PAULINO, L.(2), AZEVEDO, R.B.(2), KYAW, C.M.(3), MAGALHÃES, A.V.(4), SCHWARTZ, E.F.(1)

(1)Laboratório de Toxinologia, (2)Laboratório de Morfologia e Morfogênese, (3)Laboratório de Microbiologia, (4)Departamento de Patologia, Universidade de Brasília, (5)Hospital Regional da Asa Norte, Brasília, DF, Brasil.

Introduction: Wound dressings are thought to promote healing. The goal of the present study was to verify the physical and biological properties of a dressing derived from the amphibian Rana catesbeiana skin (Ranafilm) and that has been used at Hospital Regional da Asa Norte, Brasilia, DF, Brazil. Methods The resistance to water loss was evaluated by the weight variation of flasks filled with saline solution and covered with Ranafilm or other commercial dressings. The evaluation of resistance tension was made by dynamometer. To the healing test, three small burns were made in rabbits dorsum after anesthesia. After dehybridization, one wound was treated with Ranafilm, another one with silver sulfadiazine cream and the third one did not receive treatment. Biopsies of the wounds were done at different stages and were immediately fixed for histology. Ranafilm was extracted with 1% acetic acid and the obtained extract was tested against Staphylococcus aureus, Escherichia coli, Acinetobacter baumani, Proteus mirabilis, Klebsiela pneumoniaee Pseudomonas aeruginosa. The hemolytic activity was evaluated on human red blood cells. Results Ranafilm was the coverage with lowest capacity of water retention and demonstrated more resistance than the most of synthetic dressings. Clinical observation and histology revealed that wounds treated with Ranafilm showed faster recuperation than ones without treatment. Ranafilm extract was capable to inhibit the growth of all bacteria used, but did not presented hemolytic activity. Discussion Although Ranafilm showed minimal resistance to water loss, it holds several benefic properties that enhance wound healing such as the property of working as a framework to cell proliferation, and the antimicrobial activity. The last one is probably related to the skin bioactive compounds which have been extensively studied by several groups.

Support: DPP-UnB, CNPq

CORRESPONDENCE TO:

E.N.F. SCHWARTZ, Laboratório de Toxinologia, Universidade de Brasília, Asa Norte, 70910-900, Brasília, DF, Brasil, Email: efschwa@unb.br