Steroid-induced regulation of gene involved in the osteogenesis and adipogenesis of human bone marrow mesenhymal stem cells

Objective To observe the effect of steroid on the expression of adipogenic transcription factor,peroxisome proliferator-actived receptor-γ(PPARγ) mRNA and osteocalcin mRNA in human bone marrow mesenchymal stem cells (hBMSCs). Methods Bone marrow was aspirated from the healthy volunteers, ,and then the cells were cultured in vitro. The hBMSCs were isolated and obtained after the first passage, and then were divided into two groups. The cells were treated for 5 days with or without 10-7 mol/L dexamethasone after 8 days in the culture. The expression of PPARy mRNA and osteocalcin mRNA in the hBMSCs of two groups was detected by RT-PCR technique. Results The results of RT-PCR showed the expression of PPARy mRNA in the cells treated with dexamethasone was signifi-cantlly higher than that in the cells treated without dexamethasone (P0.01).The expression of osteocalcin mRNA in the cells treated with dexamethasone was significantlly lower than that in the cells treated without dexamethasone (P0.01).Conclusion Dexamethasone could induce overexpression of the adipogenesic gene in hMSCs,and inhibit the osteogenic gene expression, which might be contributive to the steroid-induced osteonecrosis.