Pharmaceutical application of frog skin on full-thickness skin wound healing in mice

Context: It has been proved that fresh frog skin is efficient in the wound healing process. Objective: The purpose of study is to introduce a formulation of frog skin powder for evaluation of wound repair where fresh frog skin is not available. Materials and methods: Rana ridibunda (Ranidae) skins were lyophilized, and a powder was prepared. The powder (0.0005 g) was then mixed with ointment (0.0065 g) for treating each wound. Formulation was used on full-thickness wounds on mice (FO group) and compared to positive and negative controls. In order to study the wound healing process, wound contraction, inflammation, number of fibroblast cells, neovascularization and collagen density were evaluated on days 2, 4 and 6 following the injury. Moreover, CFU measurement was performed for the evaluation of wound contamination. Results: Acceleration in wound contraction in the FO group compared to control groups was significant (p<0.001) on days 4 and 6. Results showed that FO treatment considerably decreased inflammatory cells during the study. On day 4, FO treatment was significantly effective in increasing the number of fibroblast cells and collagen density (p<0.01 and p<0.05, respectively). On day 6 the number of fibroblast cells (p<0.001), collagen density (p<0.05) and neovascularization (p<0.05), were higher in the FO group than the control groups. Results of CFU measurement demonstrated significant reduction of wound contamination in FO treated wounds on days 2 (p<0.05) and 4 (p<0.01). Discussion and conclusion: Our findings indicated that the pharmaceutical form of frog skin used in this study has considerable healing and antibacterial effects on wounds.