Salivary biomarkers of bone turnover in response to biomaterials

Abstract

Introduction: Bone regeneration involves osteoblasts, osteocytes, and osteoclasts, playing a vital role in healing processes. Saliva, a non-invasive sample for PCR, contains biomarkers for monitoring bone turnover markers (BTM), making it a valuable tool for enhancing diagnosis and treatment in periodontics through non-invasive analysis. Goal: This thesis aims to detect and quantify osteogenic biomarkers in vitro, creating a monitoring panel to validate these biomarkers as reliable indicators of bone remodelling, with the intent to apply this approach to saliva samples. Materials and Methods: Study Design: Ethical approval was granted in October 2023, the longitudinal study collects data at 0, 3, and 6 months with informed consent. Inclusion Criteria: Participants include those aged 18+ from the post-graduation course of Implantology at the Faculty of Dental Medicine, Universidade Católica Portuguesa, needing grafts or substitute treatments as identified by orthopantomography. Data collection involved the analysis of orthopantomographic images, administration of questionnaires, and saliva sampling using the passive drooling technique. The relative expression levels of OPG, RANK, RANKL, and GAPDH in MC3T3 cells, treated for 7 days with OSSIX® Plus Ossifying Collagen Barrier Membrane, were quantified using the commercial kit NZYSpeedy qPCR Green Master Mix 2x (MB22401), from NZYtech. Additionally, the expression levels of Alpl, Runx2, Col1a1, and Bglap genes were quantified in untreated MC3T3 cells. Results: The study involved 11 patients (6 females, 5 males) average age 51.82 years), revealing reduced radiolucency at treatment sites, indicating bone regeneration. RT-PCR assays from MC3T3 treated cells with collagen membranes confirmed overexpression of OPG, RANK, RANKL genes, while differential expression of GAPDH was not detected. In vitro gene expression conditions for Alpl, Runx2, Col1a1, and Bglap were optimized in untreated MC3T3 cells. Conclusion: These findings indicate that these genes could serve as salivary biomarkers for non-invasive bone regeneration, warranting further research.

Date of Award	9 Sept 2024
Original language	English
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Ana Sofia Duarte (Supervisor), Rita Noites (Co-Supervisor) & Tiago Marques (Co-Supervisor)