Cytotoxic effects of zoledronic acid on human epithelial cells and gingival fibroblasts.
Bisphosphonate-induced osteonecrosis has been related to the cytotoxicity of these drugs on oral mucosa cells. A previous study showed that 5 µM of zoledronic acid (ZA), a nitrogen-containing bisphosphonate, is the highest concentration of this drug found in the oral cavity of patients under treatment. Therefore, in order to simulate an osteonecrosis clinical condition, the aim of this study was to evaluate the highest concentration of ZA applied on human epithelial cells (HaCaT) and gingival fibroblasts. For this purpose, cells (3 × 10(4) cells/cm2) were seeded in wells for 48 h using complete culture medium (cDMEM). After 48 h incubation, the cDMEM was replaced by fresh serum-free culture medium (DMEM-FBS) in which the cells were maintained for additional 24 h. Then, 5 µM ZA were added to the DMEM-FBS and the cells incubated in contact with the drug for 48 h. After this period, the number of viable cells (trypan blue), cell viability (MTT assay), total protein (TP) production and cell morphology (SEM analysis) were assessed. Data were analyzed statistically by Mann-Whitney, ANOVA and Tukey's test (α=0.05). ZA caused a significant reduction in the number of viable cells and decreased the metabolic activity of both cell lines. However, decrease of TP production occurred only in the epithelial cell cultures. Morphological alterations were observed in both cell types treated with ZA. In conclusion, ZA (5 µM) was cytotoxic to human epithelial cells and gingival fibroblast cultures, which could be associated, clinically, with the development of bisphosphonate-induced osteonecrosis.
UNICAMP - University of Campinas, Piracicaba School of Dentistry, PiracicabaSP, Brazil.
Fernanda Gonçalves
FG
Basso
UNESP - Univ Estadual Paulista, Araraquara School of Dentistry, AraraquaraSP, Brazil.
Taisa Nogueira
TN
Pansani
Laboratory of Genetics, Butantan Institute/Departament of Morphology of UNIFESP - Federal University of São Paulo, São PauloSP, Brazil.
Camila Fávero
CF
de Oliveira
UNESP - Univ Estadual Paulista, Araraquara School of Dentistry, AraraquaraSP, Brazil.
Ana Paula Silveira
AP
Turrioni
UNESP - Univ Estadual Paulista, Araraquara School of Dentistry, AraraquaraSP, Brazil.
Diana Gabriela
DG
Soares
UNESP - Univ Estadual Paulista, Araraquara School of Dentistry, AraraquaraSP, Brazil.
Josimeri
J
Hebling
UNESP - Univ Estadual Paulista, Araraquara School of Dentistry, AraraquaraSP, Brazil.
Carlos Alberto de Souza
CA
Costa
D059266:Bisphosphonate-Associated Osteonecrosis of the Jaw / Q000209:etiology; D050071:Bone Density Conservation Agents / Q000633:toxicity*; D002452:Cell Count; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004164:Diphosphonates / Q000633:toxicity*; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000187:drug effects*; D005347:Fibroblasts / Q000187:drug effects*; D005881:Gingiva / Q000166:cytology*; D006801:Humans; D007093:Imidazoles / Q000633:toxicity*; D066298:In Vitro Techniques; D008855:Microscopy, Electron, Scanning; D000077211:Zoledronic Acid
D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D007093:Imidazoles; D000077211:Zoledronic Acid