Abstract: Objective To observe the relationship between Notoginsenoside R1(NGR1) and osteoblasts. Methods The osteoblastic progenitor cells MC3T3E1 were cultivated in alpha MEM culture medium containing 10%FBS (GibcoTM Invitrogen). Different concentrations and different kinds of NGR1 were added for searching the effect of NGR1 on osteoblasts in vitro. The following were measured in this experiment: quantitative fluorescence methods were used to detect cell proliferation; cell osteogenic differentiation alkaline phosphatase (ALP) activity was detected by colorimetric; OCN content in the medium was assayed through enzymelinked immunosorbent assay (ELISA). The expression level of each gene was calibrated through realtime fluorescence quantitative RTPCR detection, and the expression level of housekeeping beta actin gene was taken as an internal reference. Results When the concentration of NGR1 was 50 mg/L,it could significantly promote cell proliferation, but the effect of increasing concentration decreased, more than 100 had the function of inhibiting cell proliferation; when the concentration of NGR1 was 50 mg/L, it could significantly promote the activity of ALP, with the increasing of NGR1 concentration, the activity of ALP increased, and reached a plateau after the fall. NGR1 upregulated early, the expression of OCN was not significantly different, the expression of OCN increased when the concentration of NGR1 (5200 mg/L) was upregulated after 7 days. There was no significant difference in the overall expression on the 7th day, however on the 7th day at the concentration of 200 mg/L the most significant effect was induced; NGR1 significantly promoted the proliferation of osteoblasts, and gradually increased with the increasing of the concentration of NGR1. Conclusion NGR1 at fixed concentrations can promote osteoblasts proliferation.

Key words: NGR1, in vitro, osteoblasts, gene expression