Effect of simvastatins and estrogen combination on osteoblasts in rats

Objective: To study the combinational effects of simvastatins and estrogen on differentiation and the capability of mineralization of rat osteoblasts and to explore the mechanism of bone formation stimulated by simvastatins and estrogen cooperatively. Methods: Bone marrow stromal cells were isolated from four-week-old female Sprague-Dawley rats and cultured in DMEM medium to be induced into osteoblasts. They were cultured in medium with both simvastatins and estrogen at different concentrations. ALP activity and type-I pro-collagen of osteoblasts were examined by PNPP and the level of hydroxyproline was assayed. The capacity of mineralization was measured by counting bone nodules. Results: The alkaline phosphatase activity and the level of hydroxyproline of osteoblasts increased , and the number of nodules was significantly higher. Conclusions: Simvastatins and estrogen can increase the capability of differentiation and mineralization of osteoblasts cooperatively.