title: The incorporation of Brazilian propolis into collagen-based dressing films improves dermal burn healing.
abstract: BACKGROUND
  Hydroalcoholic solutions of propolis, a resinous product produced by bees, have been currently employed in improving the cicatricial repair. Biological activity of propolis might be related to its antimicrobial, anti-inflammatory and immunomudalatory properties.
  
  
  OBJECTIVE
  Investigate the suitability of the collagen-based films containing hydroalcoholic extracts of two different varieties of Brazilian propolis (green and red ones) on the dermal burn healing in rodent model.
  
  
  METHODS
  The hydroalcoholic extracts of red propolis (RP) or Green propolis (GP) were incorporated into collagen-based dressing films (COL). Burn wounds were performed in the dorsum of Wistar rats and dressing with COL, COL+GPa (0.5%), COL+GPb (1,0%) or COL+RP (0.5%). A control group (CTR) was performed keeping the wound undressed. The histological analyses were carried out after 3, 7, 14, 21 and 30 days for histological assessment of the inflammatory response, epithelization rates (ER), myofibroblastic count (MC) and collagenization pattern.
  
  
  RESULTS
  GPa, GPb and RP provided significant decrease of the inflammatory severity, improved the ER in GPa in 7 (p=0.000), 14 (p=0.000), 21 (p=0.005) and 30 days (p=0.015), and induced earlier replacement of type-III for type-I collagen (p<0.05) than COL and CTR. In all the groups, the MC increased progressively from 3 to 14 days, and then started to decrease slowly until 21 days. Although no significant difference was observed among the groups in 3, 7 and 30 days, the MC was significantly increased in RP in 14 (p=0.0001) and 21 days (p=0.04), as well as grosser interlacement of the collagen bundles compared with the other groups.
  
  
  CONCLUSIONS
  The incorporation of hydroalcoholic extracts of Brazilian propolis improved the biological events associated to burn healing without toxic effects, but the red variety provided the best results. Therefore, these collagen-based containing natural apicultural products films may be considered a promising new dressing for wound occlusion and tissue repairing.
authors.affiliation: University Tiradentes, Aracaju/SE, Brazil. enrik_almeida@yahoo.com.br
authors.forename: Enrik Barbosa
authors.initials: EB
authors.lastname: de Almeida
authors.forename: Juliana
authors.initials: J
authors.lastname: Cordeiro Cardoso
authors.forename: Adriana
authors.initials: A
authors.lastname: Karla de Lima
authors.forename: Nívia Lucas
authors.initials: NL
authors.lastname: de Oliveira
authors.forename: Nicodemos Teles
authors.initials: NT
authors.lastname: de Pontes-Filho
authors.forename: Sônia
authors.initials: S
authors.lastname: Oliveira Lima
authors.forename: Isana Carla
authors.initials: IC
authors.lastname: Leal Souza
authors.forename: Ricardo Luiz Cavalcanti
authors.initials: RL
authors.lastname: de Albuquerque-Júnior
mesh_terms: D000818:Animals; D001458:Bandages; D001688:Biological Products / Q000008:administration & dosage*; D001938:Brazil; D002056:Burns / Q000188:drug therapy*; D002454:Cell Differentiation / Q000187:drug effects; D003094:Collagen / Q000008:administration & dosage*; D005419:Flavonoids / Q000032:analysis; D008297:Male; D058628:Myofibroblasts / Q000166:cytology / Q000187:drug effects; D011429:Propolis / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar; D012867:Skin / Q000293:injuries; D014945:Wound Healing / Q000187:drug effects*
chemical_list: D001688:Biological Products; D005419:Flavonoids; D003094:Collagen; D011429:Propolis