• José B Alves, Cynthia L Ferreira, Aline F Martins, Gerluza A B Silva, Guilherme D Alves, Tony P Paulino, Pietro Ciancaglini, Geraldo Thedei, and Marcelo H Napimoga.
• Laboratory of Molecular Biology, University of Uberaba, Uberaba, MG, Brazil. propg.pr@uniube.br
• Life Sci. 2009 Nov 4; 85 (19-20): 693-9.

AimsIt has long been demonstrated that epidermal growth factor (EGF) has catabolic effects on bone. Thus, we examined the role of EGF in regulating mechanically induced bone modeling in a rat model of orthodontic tooth movement.Main MethodsThe maxillary first molars of rats were moved mesially using an orthodontic appliance attached to the maxillary incisor teeth. Rats were randomly divided into 4 groups: (G1) administration of PBS (phosphate buffer saline) solution (n=24); (G2) administration of empty liposomes (n=24); (G3) administration 20ng of EGF solution (n=24); and (G4) 20ng of EGF-liposomes solution (n=24). Each solution was injected in the mucosa of the left first molar adjacent to the appliance. At days 5, 10, 14 and 21 after drug administration, 6 animals of each group were sacrificed. Histomorphometric analysis was used to quantify osteoclasts (Tartrate-resistant acid phosphatase (TRAP)+cells) and tooth movement. Using immunohistochemistry assay we evaluated the RANKL (receptor activator of nuclear factor kappaB ligand) and epidermal growth factor receptor (EGFR) expression.Key FindingsThe EGF-liposome administration showed an increased tooth movement and osteoclast numbers compared to controls (p<0.05). This was correlated with intense RANKL expression. Both osteoblasts and osteoclasts expressed EGFR.SignificanceLocal delivery of EGF-liposome stimulates osteoclastogenesis and tooth movement.

26 keywords...

hide…