Sirt1促进炎症牙周膜干细胞成骨分化的机制

The study of Sirt1 promotes the osteogenic differentiation of inflammatory PDLSCs

目的探讨去乙酰化酶1(Sirt1)对炎症牙周膜干细胞(PDLSCs)成骨分化的作用,并研究其可能的分子机制。方法分离、培养正常及炎症PDLSCs,观察Sirt1在两种细胞中的表达;将炎症PDLSCs进行成骨诱导,同时使用Sirt1激动剂白芦藜醇上调炎症PDLSCs中的Sirt1,观察炎症PDLSCs的成骨分化情况,Western blot检测Runx2、乙酰化NF-κB、乙酰化FoxO1和FoxO1的表达。结果炎症PDLSCs中Sirt1的表达较正常PDLSCs减少(P<0.01);白芦藜醇可上调炎症PDLSCs中Sirt1的表达;与成骨诱导组比较,成骨诱导+白芦藜醇组炎症PDLSCs中BSP(t=14.045,P<0.01)、Runx2(t=3.349,P<0.01)、OCN(t=7.218,P<0.01)和Osx(t=4.544,P<0.01)mRNA的表达增加,ALP染色增强(P<0.01);炎症PDLSCs成骨诱导后FoxO1(t=8.737,P<0.01)和Runx2(t=6.152,P<0.01)的表达增强;使用白芦藜醇上调Sirt1的表达后,FoxO1(t=5.912,P<0.01)和Runx2(t=6.277,P<0.01)的表达较成骨诱导组进一步增加,而乙酰化NF-κB(F=184.033,P<0.01)和乙酰化FoxO1(F=301.454,P<0.01)的表达较对照组和成骨诱导组明显降低。结论去乙酰化酶Sirt1可以通过去乙酰化NF-κB和FoxO1,从而促进炎症PDLSCs的成骨分化。

Objective To study the positive effect and mechanism of histone deacetylase Sirtuin 1(Sirt1)on the osteogenic capacity of inflammatory PDLSCs.Methods PDLSCs were isolated and cultured from the healthy individuals and periodontitis patients,the expression of Sirt1 in two types of PDLSCs was observed;osteogenic induction of inflammatory PDLSCs was performed,concurrently Sirt1 agonist resveratrol was used to up-regulate the expression of Sirt1,then the osteogenic differentiation was observed,the expressions of Runx2,acetylated NF-κB,acetylated FoxO1 and FoxO1 were assessed by Western blot.Results The protein expression of Sirt1 was suppressed in inflamed PDLSCs(P<0.01);resveratrol could up-regulate the expression of Sirt1 in inflamed PDLSCs;compared with the osteogenic induction group,the osteogenesis+resveratrol group increased the expression of BSP(t=14.045,P<0.01),Runx2(t=3.349,P<0.01),OCN(t=7.218,P<0.01)and Osx(t=4.544,P<0.01)mRNA in inflamed PDLSCs,and enhanced ALP staining(P<0.01);expression of FoxO1(t=8.737,P<0.01)and Runx2(t=6.152,P<0.01)increased after osteogenesis of inflamed PDLSCs;in the osteogenesis+resveratrol group,the expression of Sirt1 was up-regulated,and the expression of FoxO1(t=5.912,P<0.01)and Runx2(t=6.277,P<0.01)further increased compared with the osteogenic induction group,while the expression of acetylated NF-κB(F=184.033,P<0.01)and acetylated FoxO1(F=301.454,P<0.01)was significantly lower than that of control group and osteogenic induction group.Conclusion The deacetylase Sirt1 could promote the osteogenic differentiation of inflammatory PDLSCs through deacetylating NF-κB and FoxO1.