1334 Gene expression of osteogenic cells exposed to calcium aluminate cement

Saturday, March 24, 2012: 9:45 a.m. - 11 a.m.
Presentation Type: Poster Session
L.M.S.D. CASTRO-RAUCCI1, L.N. TEIXEIRA2, W. RAUCCI-NETO1, R.R. FERNANDES1, F.S.D. OLIVEIRA1, M. JACOBOVITZ3, A.L. ROSA1, and P.T.D. OLIVEIRA1, 1School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil, 2School of Dentistry of Piracicaba, State University of Campinas, Piracicaba, SP, Brazil, 3Paulista Association of Dental Surgeons, São Carlos, SP, Brazil
Objective: The aim of this study was to evaluate the effect of a novel calcium aluminate cement (CAC+) on gene expression of key osteoblastic markers in primary osteogenic cell cultures.

Method: Osteogenic cells were enzimatically isolated from newborn rat calvarial bone, plated on Thermanox coverslips at 20,000 cells/well, and cultured for up to 10 days. CAC+ and mineral trioxide aggregate (MTA) specimens (4 mm in diameter and 2 mm height) were prepared according to manufacturer’s guidelines under sterile conditions and allowed to solidify in silicon templates for 4 hours. CAC+ and MTA specimens were placed on polycarbonate inserts (pore size, 3 µm) and cell exposure was performed during either the proliferative (days 2-5) or the differentiation phase (days 7-10). Gene expression of runt-related transcription factor 2 (RUNX-2), alkaline phosphatase (ALP), osteocalcin (OC), osteopontin (OPN), bone sialoprotein (BSP), and osterix (OST) was assessed by means of Real-Time PCR at days 7 and 10. Comparisons were carried out using the non-parametric Kruskal-Wallis test (p < 0.05).

Result: At day 7, cultures exposed to CAC+ during the proliferative phase exhibited a higher gene expression of RUNX-2, ALP, and BSP, while OPN expression was greater in cultures exposed to MTA. At day 10, a higher expression of RUNX-2, ALP, OC, BSP, and OST was noticed for cells exposed to CAC+ during the proliferative phase. Cultures exposed to CAC+ at differentiation phase showed a greater expression of RUNX-2 and BSP, whereas those exposed to MTA exhibited a higher expression of OPN.

Conclusion: These results indicate that CAC+ supports the up-regulation of key markers of osteoblastic differentiation in osteogenic cell cultures irrespective of the timing of exposure.

This abstract is based on research that was funded entirely or partially by an outside source: The State of São Paulo Research Foundation (FAPESP), grants 2009/53310-1 and 2010/50936-4

Keywords: Bone, Cell culture, Cements, Endodontics and Gene expression