Effects of genistein on proliferation of osteoblast of post-menopausal patients and the likely molecular mechanisms

Objective This study was designed to explore the effects of phytoestrogen genistein on proliferation of post-menopausal osteoblast and the likely molecular mechanisms. Methods Osteoblast cultures were prepared from the upper femur of postmenopausal patients. Osteoblast proliferation was determined by Methyl Thiazolyl Tetrazolium(MTT)assay and cell cycle distribution by cytometry. The protein expressions of cyclin D and E were examined using Western-blot. Results Genistein (10~(-8) to 10~(-6) mol/L) stimulated cell viability of postmenopausal osteoblasts and increased the distribution ratio of the cells at the G2/M and S phases (P0.05) with a slight decrease in G0/G1 population. Osteoblasts demonstrated two- and fourfold increased cyclin D expression when treated with 10~(-8) mol/L (P 0.05) and 10~(-7) mol/L (P0.01) GS, respectively, as compared with untreated cells. The changes of cyclin E expression at protein level were similar with cyclin D. Conclusions Taken together, these results suggested that flavonols genistein could stimulate osteoblast activity via an estrogen-receptor-dependent pathway. Such compounds may represent new pharmacological tools for the treatment of osteoporosis.