Analysis Of The Expression Of Osteoprotegerin On Osteoblasts And Osteogenetic Effects By Icariside â…¡via P38MAPK Pathwayin Vitro

Objective The aim of this article is to study the effect of Icariside II on osteoprotegerin(OPG) expression which plays a significant role in osteoporosis, and the relation between p38 MAPK signaling pathway and OPG expression in osteoblasts. Explore the mechanism of ICA II therapy in osteoporosis treatment.Methods Primary osteoblasts were cultured and randomizeds separated into four groups:control group(Group C), group Icariside II,mixed group(ICA II+SB203580),group SB203580(P38 signaling pathway inhibitor).ALP activity levels were detected by p NPP method. The protein levels of p38MAPK、p-p38 MAPK and OPG were measured by Western-blot. The expression of OPG m RNAs were detected by RT-PCR. Pearson was used to analysis the results.Results1 Changes of ALP activity of osteoblasts Cells exposed to ICA II showed a significantly increase in the level of ALP activity(P<0.05). While SB203580 inhibited the high level of ALP activity in group M, compared to group ICA II(P<0.05). 2 Level of p38 MAPK and p-p38 MAPK protein expression in osteoblasts Levels of p-p38 MAPK in group ICA II were remarkablyhigher than that of group C(P<0.05). The p-p38 MAPK level was significantly decreased in group M added with SB203580. Among all of the groups, the total p38 MAPK protein level kept unchanged. 3 Changes of OPG protein expression in osteoblasts The level of OPG in group C was remarkably lower than group ICA II(P<0.01).Treatment with SB203580 in group M markedly inhibited the high OPG expression in osteoblasts, compared with group ICA II(P<0.01). 4 Changes of OPG m RNA expression in osteoblasts Compared with group C, the gene expression level of OPG were significantly upregulated after exposing to Icariside II for 48h(P<0.01).SB203580 markly suppressed the upregulation, as the results reflected in group M.(P<0.01). 5 Correlation analysis Pearson in SPSS shows thephosphorylatedp38 MAPK level was evidently correlated to ALP、OPG m RNA expression and OPG secretion(P<0.01).Conclusion The expression level of OPG m RNA and OPG were siginificantly increased in group added with Icariside II, while SB203580 can inhibit the expression level via p38 MAPK. Icariside II can cure osteoporosis by stimulating OPG expression and promoting the differentiation of osteoblasts. The effect of Icariside II on osteoblasts may be related to p38 MAPK signaling pathway.