Platelet-rich plasma versus dexamethasone in inhibiting effect on osteogenic differentiation of human bone marrow mesenchymal stem cells

Abstract

Objective To compare the effects of platelet-rieh plasma (PBP) and dexamethasone (DEX) on osteogenic differentiation of human bone marrow mesenchymal stromal cells (BMSCs). Methods BMSCs cultured in vitro were divided to 3 groups: fetal calf serum group (FCS group), PRP group (human BMSCs treated by PRP), and DEX group (human BMSCs treated by DEX) . Inverted phase contrast mi-croscopy, alkaline phosphate (ALP) staining, calcium staining and RT-PCR were used to determine gene expressions of ALP, osteocalcin (OC), collagen type Ⅰ (Coll-Ⅰ), osteonectin (ON), and core binding factor alpha 1 (Cbfα1) . The effects of PRP on osteogenic differentiation of human BMSCs were evaluated and compared with those of DEX. Results Most of the BMSCs treated by DEX were triangle or polygon in form while those treated by PRP were fusiform. At day 7, compared with FCS group, the number of ALP-positive cells in PRP group decreased (P < 0.05), but increased in DEX group (P < 0.05). At day 19, there was a significant difference in mineral deposition between PRP and FCS groups, with few calcium nodes in the PRP group (P < 0.05) . Compared with FCS group, treatment of Human BMSCs with DEX markedly increased mineral deposition, leading to much more calcium nodes (P < 0.05). DEX resulted in an earlier expression of OC at day 7 compared with FCS, and increased OC mRNA expressions at other culture time points. At the same time, DEX up-regulated ALP mRNA expression. Compared with FCS group, PRP decreased OC and ALP mRNA expressions. At different time points, the expressions of Cbfα1, ON, and Coll-Ⅰ mRNA showed no significant changes in the 3 groups. Conclusion PRP may have a direct effect on inhibiting osteogenic differentiation of human BMSCs, and can not be a substitute of DEX as an agent of osteogenic differentiation in vitro. Key words: Platelet-rich plasma; Bone mesenchymal stromal cells; Dexamethasone; Differentiation