STUDY ON MECHANISM OF SIMVASTATIN IN PROMOTING RAT BMSCS OSTEOBLASTIC DIFFERENTIATION

[Objective] To investigate the stimulating effect of simvastatin on osteogenic differentiation of bone marrow stromal sells (BMSCs) of SD rats. [Methods] BMSCs derived from the tibia and femur of 4-week old female SD rats were cul- tured in vitro under osteoblastic-induced differentiation since the first subculture (8th day) and divided into 2 groups: control group (N), SIM treated group (SIM) .The cells of 1st subculture in SIM group were treated with SIM (10-7mol / L), cells in group N were treated with vehicle as control. Alkaline phosphatase (ALP) staining was applied at the 16th day and von Kossa staining was performed at 28th day to assess the osteoblastic differentiation and mineralization.Real time RT-PCR was performed to evaluate the expressions of b-catenin, BMP-2, Smad1, ALP, OCN mRNA at the two time points. [Results] ① SIM increased the expression of ALP and promoted the matrix mineralization. ② mRNA expression: At 16th day, the expression of ALP increased significantly in SIM group compared to N group; at 28th day, expression of BMP-2, Smad1, OCN in SIM group were significantly higher and b-catenin was significantly lower than those of group N (P﹤0.05). [Conclusion] SIM could promote the osteogenic differentiation of BMSCs, changes of the mRNA expression levels in some components of TGFβ / BMP and WNT signaling pathway might participate in this progress.