锶可通过激活Notch信号通路促进脂肪来源干细胞成骨分化

Promotion of osteoblastic differentiation of ADSCs by strontium through activating the Notch signaling pathway

目的探讨锶(strontium,Sr)促进脂肪来源干细胞成骨分化过程与Notch信号通路的关系。方法于2017年1~4月,对脂肪来源干细胞进行分离、提取、鉴定,行成骨诱导,按实验目的分组处理后,以酶标法检测成骨标记物碱性磷酸酶(alkaline phosphatase,ALP)活性,Western blot检测各组Notch信号通路相关蛋白Notch胞内结构域(notch intracellular domain,NICD)表达情况。结果 100μmol/L SrCL_2可增加ALP活性,上调NICD蛋白表达,当加入Notch通路抑制剂γ分泌酶抑制剂(DAPT)后,可抑制锶对NICD蛋白上调作用,拮抗锶对ALP活性的促进作用,削弱脂肪来源干细胞成骨分化能力。结论锶可通过激活Notch信号通路促进脂肪来源干细胞成骨分化。

Objective To explore the relationship between the promotion of osteogenic differentiation of adipose-derived stem cells by strontium（Sr） and the Notch signaling pathway. Methods From January to April 2017, ADSCs were isolated, extracted, identified, and induced for osteogenesis. Based on different experimental objectives, the ADSCs were divided into four groups. The activity of alkaline phosphatase（alkaline phosphatase, ALP） was measured by enzyme labeling. The expression of the Notch intracellular domain（NICD） of the associated protein of the Notch signaling pathway in each group was detected by Western Blot. Results The activity of ALP increased and the expression of NICD protein up-regulated when SrCL2 was 100 μmol/L. After adding γ-secretase inhibitor（DAPT） of inhibitor to the Notch pathway, the up-regulation of SrCL2 to NICD protein was inhibited. The promotion of ALP activity by strontium was antagonized with the introduction of DAPT and the osteogenic differentiation ability of the ADSCs was weakened. Conclusion The osteogenic differentiation of ADSCs can be activated by strontium through the Notch signaling pathway.