title: Topical effects of frog "Rana ridibunda" skin secretions on wound healing and reduction of wound microbial load.
abstract: BACKGROUND
  Study of the interrelationships between human and the animals in their environment has always been a subject of interest and caused discoveries of the animal applications in medicine. From the latest century, these remedies called back in traditional medicine of Vietnam and South America and frog skin was used as a biological dressing and had good effects in healing wounds. Also, frog skin secretions have wound healing properties and reduce inflammation. In this study we applied these secretions in the form of ointment to investigate their healing activities.
  
  
  METHODS
  Skin secretions were extracted from Rana ridibunda to evaluate their effects on wound healing in mice. Secretion used as raw extract (RE) and ultrafiltrated extract, using a membrane with cutoff 10kDa as under 10kDa (U10E), was administrated as ointment every 48h on wound site. Control group was left without any treatment and also there was other group treated with ointment (O group) alone. On 2, 4 and 6 days post injury, animals were euthanized and images were taken for wound closure evaluation. Then wound locations were removed for histological assays. Also wound microbial load was examined. Observational parameters including wound closure and wound microbiology in experimental groups compared with the control and O groups have been studied.
  
  
  RESULTS
  The results showed U10E group has better effects than RE, O and control groups. Histological parameters, including numbers of inflammatory and fibroblast cells and amount of collagen fibers, neovascularization, as well, represented greater degree of wound healing in U10E group compared with RE, O, and control groups.
  
  
  CONCLUSIONS
  Our results showed that frog skin secretions were significantly effective in promoting wound healing process. The U10E extract from the frog R. ridibunda possesses a potent accelerating wound healing effect that promises good potential for clinical application in wound care. Further studies will be required to characterize special molecules encompassing healing properties.
authors.affiliation: Department of Biology, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran. mmashreghi3@gmail.com
authors.forename: Mohammad
authors.initials: M
authors.lastname: Mashreghi
authors.forename: Mahere
authors.initials: M
authors.lastname: Rezazade Bazaz
authors.forename: Nasser
authors.initials: N
authors.lastname: Mahdavi Shahri
authors.forename: Ahmad
authors.initials: A
authors.lastname: Asoodeh
authors.forename: Mansour
authors.initials: M
authors.lastname: Mashreghi
authors.forename: Morteza
authors.initials: M
authors.lastname: Behnam Rassouli
authors.forename: Shiva
authors.initials: S
authors.lastname: Golmohammadzadeh
mesh_terms: D000287:Administration, Topical; D000818:Animals; D058491:Bacterial Load / Q000187:drug effects; D045424:Complex Mixtures / Q000627:therapeutic use*; D008297:Male; D051379:Mice; D018919:Neovascularization, Physiologic / Q000187:drug effects; D009824:Ointments; D011895:Rana ridibunda; D012867:Skin / Q000098:blood supply / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D014945:Wound Healing / Q000187:drug effects*
chemical_list: D045424:Complex Mixtures; D009824:Ointments