Effect of bisphosphonates on the metalloproteinases expression and activity by gingival fibroblasts seeded on titanium surfaces

• Grant number: 16/23610-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2017
• End date: December 31, 2017
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Fernanda Gonçalves Basso
• Grantee: Isabela Massaro Ribeiro
• Host Institution: Universidade de Ribeirão Preto (UNAERP). Campus Ribeirão Preto. Ribeirão Preto , SP, Brazil

Abstract

Bisphosphonates are indicated for metabolic and neoplastic bone diseases to control the resorption of of bone tissue. These drugs show high adhesion to mineral tissues and after a traumatic or inflammatory event they can be released and can act by inducing the apoptosis of osteoclats and also inhibiting the maturation of these cells. The installation of osteointegrated implants on patients under bisphosphonates treatment is controversial, due to the fact that a local injury can lead to the development of an osteonecrotic area. Recent studies demonstrated that these patients can show distinct outcomes after the installation of oral implants, from a better osteointegration to implants failure. However, few is known about the factors that can be determinant for the success of oral implants on these patients. One of these factors can be the type of bisphosphonate used, which is directly related to its potency, administration route and concentration. These factors can influence on the response of bone tissue following the installation of osteointegrated implants, since previous investigations demonstrated that these drugs can negatively affect the metabolism of oral mucosa cells, inhibiting the formation of an effective biological sealing. One of the main events that can affect this response is the increased expression, synthesis and activity of metaloproteinases. Therefore, the aim of this investigation will be to evaluate the effect of two bisphosphonates, zoledronic acid (ZA) and sodium alendronate (SA) on the activity of metaloproteinases by gingival fibroblasts seeded onto titanium surfaces. Titanium discs will be placed on cell culture plates and gingival fibroblasts will be seeded onto these discs. After 24 hours, cells will be exposed to different concentrations of both bisphosphonates (0,5, 1 e 5 ¼M). After 48 hours, the synthesis of MMP-2 will be determined by ELISA immunoassay, while gelatonolytic activity will be determined by in situ zymography. (AU)