Effect of zoledronic acid and/or denosumab on epithelial cell metabolism

• Grant number: 25/25689-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2026
• End date: December 31, 2026
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Taisa Nogueira Pansani
• Grantee: Ana Clara Mendonça do Nascimento
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Associated research grant: 22/06491-5 - Use of extracellular vesicles to prevent the development of osteonecrosis of the jaws: in vitro and in vivo studies, AP.GR

Abstract

Medication-related osteonecrosis of the jaws (MRONJ) is a condition characterized by necrotic bone tissue in the oral cavity of patients who have used antiresorptive drugs, such as bisphosphonates and monoclonal antibodies, without a history of head and neck radiotherapy. Bisphosphonates inhibit bone resorption by inducing apoptosis in osteoclasts, while denosumab (a monoclonal anti-RANKL antibody) blocks the differentiation of these cells. However, the accumulation of these drugs in tissues leads to reduced local vascularization, tissue toxicity, and delayed tissue repair due to cytopathic effects on connective and epithelial tissue cells. Although the incidence of MRONJ is relatively low (6.7%) in patients using intravenous zoledronic acid (ZA) and 10% in those treated with denosumab (D), the combined use of these drugs may further increase the incidence of MRONJ (15.5%). Therefore, the objective of this project is to evaluate the effects of zoledronic acid (ZA) and denosumab (D), individually or in combination, on epithelial cell metabolism. HaCat cells will be seeded in 96-well plates at a density of 1×10¿ cells/well, in DMEM culture medium supplemented with 10% fetal bovine serum (FBS). Four experimental groups will be established: untreated control (CN), ZA (5 ¿M), D (40 ¿g/mL), and ZA+D, with n=8 per group. After 24 hours of cell culture, the medium will be replaced with DMEM containing the drugs according to the groups, which will remain for 72 hours. Subsequently, analyses of cell viability, collagen synthesis, cell adhesion by fluorescence microscopy, gelatinolytic activity, and TNF-¿ and IL-6 expression (ELISA) will be performed. Data will be subjected to statistical analysis, with a significance level of 5%.