title: Effects of fluoride in bone repair: an evaluation of RANKL, OPG and TRAP expression.
abstract: The objective of this study was to evaluate comparatively the effect of fluoride in the expression of the receptor activator of nuclear factor kappa B ligand (RANKL), osteoprotegerin (OPG) and tartrate-resistant acid phosphatase (TRAP) in alveolar bone repair in rats. We used 3 groups of male Wistar rats (n = 5/group), which received drinking water containing different doses of F (NaF): 0, 5 and 50 ppm, for 60 days before the incisors extraction. The upper incisors were extracted and the animals were killed 7, 14, 21 and 30 days after extraction. The hemi-maxillae were collected for microscopic examination (histomorphometric and immunostaining for RANKL, OPG and TRAP). Histomorphometric analysis confirmed an increase in the volume density of neoformed bone between 7 and 30 days for groups control, 5 and 50 ppm of F, with a concomitant decrease in the volume density of connective tissue and blood clot. Higher blood clot for groups 5 and 50 ppm of F at 30 days was observed. The RANKL and OPG expressions were not changed by chronic exposure to fluoride in the drinking water during the studied periods; on the other hand, TRAP expression was changed (at 7 days) by chronic exposure to fluoride (p < 0.05). It was concluded that F in high concentrations can slow the blood clot remission and bone repair, and alter the TRAP expression in the beginning of the bone tissue repair. However, a better understanding about this blood clot remission phenomenon is required.
authors.affiliation: Department of Biological Sciences, Bauru Dental School, University of São Paulo (USP), Alameda Dr. Octávio Pinheiro Brisolla 9-75, Bauru, São Paulo (SP), 17012-901, Brazil.
authors.forename: Mileni da Silva
authors.initials: Mda S
authors.lastname: Fernandes
authors.forename: Marcela Mitsuko
authors.initials: MM
authors.lastname: Yanai
authors.forename: Gisele Miyamura
authors.initials: GM
authors.lastname: Martins
authors.forename: Flávia Godoy
authors.initials: FG
authors.lastname: Iano
authors.forename: Aline Lima
authors.initials: AL
authors.lastname: Leite
authors.forename: Tânia Mary
authors.initials: TM
authors.lastname: Cestari
authors.forename: Rumio
authors.initials: R
authors.lastname: Taga
authors.forename: Marília Afonso Rabelo
authors.initials: MA
authors.lastname: Buzalaf
authors.forename: Rodrigo Cardoso
authors.initials: RC
authors.lastname: de Oliveira
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism*; D000818:Animals; D001861:Bone Regeneration; D005459:Fluorides / Q000008:administration & dosage*; D007527:Isoenzymes / Q000378:metabolism*; D008297:Male; D053244:Osteoprotegerin / Q000378:metabolism*; D053245:RANK Ligand / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D000071681:Tartrate-Resistant Acid Phosphatase
chemical_list: D007527:Isoenzymes; D053244:Osteoprotegerin; D053245:RANK Ligand; C506032:Tnfrsf11b protein, rat; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase; D005459:Fluorides