Study Of Strontium Promote Osteogenic Differentiation Of Adipose-derived Stem Cells Via Notch Signaling Pathway

Objective:To investigate the effects of strontium on the osteogenic differentiation of adipose-derived stem cells?ADSCs?,we compared the activities of Alkaline phosphatase?ALP?as well as the expression of Notch intracellular domain?NICD?in Notch signaling pathway before and after inhibiting.Our objective is to explore how Sr interacts with the Notch signaling pathway to promote the osteogenic differentiation of ADSCs.Methods:ADSCs were isolated,extracted,identified,and then induced for osteogenesis.Based on different purposes,they were divided into the following four groups:SrCl₂group,SrCl₂+DAPT group,DAPT group,and Control group.After 6 days of co-culture,the activity of ALP was measured by enzyme labeling and the expression of NICD in each group was detected by western blotting.Results:1.ALP activity:In the process of osteogenic induction of ADSCs,the ALP activity of SrCl₂ group was significantly increased when treated with 100?M SrCl₂ for 6days?P<0.01?.When DAPT was added into 100?M SrCl₂ medium at the same time,the activity of ALP was lower than that of SrCl₂ group at 6^th day.The difference between SrCl₂+DAPT group and SrCl₂ group was statistically significant?P<0.05?.However,there was no significant difference in ALP activity between DAPT group and Control group?P>0.05?.2.NICD expression:In the process of osteogenic induction of ADSCs,the expression of NICD in Notch signaling pathway SrCl₂ group was significantly up-regulated compared with Control group?P<0.01?when treated with 100?M SrCl₂ for6 days.When treated with DAPT in 100?M SrCl₂ medium for 6 days,the expression of NICD protein was significantly lower than that of SrCl₂ group,the expression of NICD protein was inhibited and Notch signaling pathway was blocked.The difference between SrCl₂+DAPT group and SrCl₂ group was statistical significance?P<0.01?.Conclusion:Sr promote ADSCs osteogenic differentiation by activating Notch signaling pathway.