Profilaksa DVT kod velikih ortopedskih operacija - Depol ...

20 - 22 September 2012, Opatija, Croatia
OSTEOGENIC POTENTIAL AND STEMNESS OF MESENCHYMAL
STEM CELLS AFTER DEXAMETHASONE TREATMENT
Igor Matić, Faculty of Science, University of Zagreb, Zagreb, Croatia
Alan Ivković, Clinical Hospital Sveti Duh, Zagreb, Zagreb, Croatia
Šime Brkić, Faculty of Science, University of Zagreb, Zagreb, Croatia
Pavle Josipović, Faculty of Science, Univeristy of Zagreb, Zagreb, Croatia
Ivan Karlak, Clinic for Traumatology, Zagreb, Zagreb, Croatia
Marko Pećina, School of Medicine, University of Zagreb, Zagreb, Croatia
Inga Marijanović, Faculty of Science, University of Zagreb, Zagreb, Croatia
The purpose of the research was to improve osteogenic differentiation of human bone marrow derived-mesenchymal
stem cells (hMSCs) and to evaluate the level of remaining undifferentiated stem cells in culture. Standard
cell culture protocol includes continuous exposure to the dexamethasone which is not easy to reproduce in human
body. Therefore, our experiment was designed to investigate the possibility of using short-term dexamethasone
exposure in order to induce osteogenic differentiation.
Human bone marrow-derived MSCs were expanded with FGF-2 supplemented media. Afterwards cells were cultured
in osteogenic media (DMEM low glucose, 10% FBS, 10mM β-glycerophosphate, 5µg/ml ascorbic acid, 1mM
piruvat) and treated with different concentrations of dexamethasone, both short-term and continuous. The differentiation
status of the cells was estimated using several osteogenic markers - alkaline phosphatase (AP) activity,
the bone sialoprotein (BSP) and dentin matrix protein 1 (DMP-1) mRNAs. The stemness of the cells was estimated
by the presence of pluripotency markers - SRY (sex determining region Y)-box 2 (SOX2) and octamer-binding transcription
factor 4 (OCT4). The measurements were conducted on the days 7 and 14 after osteogenic conditions
had been introduced.
Our results show that continuous treatment induces the highest level of osteogenesis, but 2 hour exposure also induced
differentiation in comparison with control. Overall, 10-5 M concentration of dexamethasone was the most
powerful in the short-term induction of osteogenesis. SOX2 has not been detected in hMSCs. OCT4 was expressed
in undifferentiated pluripotent hMSCs and its expression subsequently went down, indicating that the differentiation
process is proceeding
Poster
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