Bone Abstracts

Constant remodeling of extracellular matrix (ECM) is a hallmark during physiological conditions, such as stem cell differentiation, embryogenesis and tissue repair. Matrix metalloproteinases (MMP) play a key role in these processes. MMPs, MMP-activator (EMMPRIN/CD147) and MMP-inhibitors (TIMPs and RECK) are responsible for bone matrix remodeling and, probably, determinate the level of its turnover. Mesenchymal stem cells derived from dental pulp are multipotent and have the capacity to differentiate into several mesenchymal tissues, such as bone, fat and cartilage, under inductive conditions in vitro. However, it is unknow In this study, we evaluated differential gene expression of MMPs (25 members), TIMPs (four members), RECK, and EMMPRIN/CD147 of dental pulp stem cells (DPSCs) exposed to osteogenic induction. DPSCs isolated from extracted human third molars (collagenase/dispase digestion at 37 °C) were grown in α-MEM medium+10% FBS and differentiation induction in presence of osteogenic medium (10 mM β-glycerophosphate, 1 mM dexamethasone, and 50 μg/ml ascorbate) for 35 days. We measured bone formation markers (osteocalcin, alkaline phosphatase, and mineral nodules) using western blot, colorimetric assay and Alizarin Red S dye, respectively, and gene expression by qRT-PCR. After osteogenic differentiation, bone formation markers, matrix mineralization and differential gene expression were observed. This is the first evidence that MMPs, TIMPs, RECK, and EMMPRIN/CD147 are differentially expressed in osteoblast differentiation from DPSCs in vitro.

Keywords: Dental pulp stem cells, MMP, TIMP, RECK, EMMPRIN/CD147, and Osteoblast Differentiation.

FAPESP.