Abstract: Objective: To investigate the effect of puerarin on the biological properties of MC3T3-E1 under high concentration of glucocorticoid circumstance through in vitro cell culture and related interventions. Methods: MC3T3-E1 preosteoblasts were cultured in vitro and divide into control group and five experimental groups, which were intervened with gradient concentration of puerarin (0, 10^-5, 10^-6, 10^-7, 10^-8, 10^-9mol/L) under high concentration of glucocorticoid circumstance (10^-6mmol/L). Cell proliferation was detected after 1 d, 4 d, and 7 d of cell culture by using the CCK-8 kit, activity of ALP was detected after 1 d, 4 d, and 7 d of cell culture by using alkaline phosphatase kit, and the expression of OPG mRNA was detected by quantitative real-time PCR after 7 d of cell culturing. The cells were stained with phalloidin after 24 h of culture and observed the cytoskeletal morphology changes under the confocal laser microscope. Results: CCK-8 showed that the difference between the control group and the experimental group was statistically significant (P<0.05), and the most obvious effect of cell proliferation was 10^-7mol/L group on the 4th day (P<0.05). ALP activity test showed that the expression of ALP in all the experimental groups increased at the same time and there was statistical significance in the difference between the experimental group and the control group (P<0.05). The results of confocal laser scanning indicated that, in group of 10^-7mol/L, the cells spread more widely and the structure was clear. PCR results showed that the expression of OPG mRNA in each experimental group was higher than that in the control group (P<0.05). Conclusion: Puerarin, under high concentration of glucocorticoid circumstance, can promote cell proliferation, extension, and differentiation of MC3T3-E1 cells.

Key words: puerarin, glucocorticoid, osteoblast, proliferation, differentiation