23-乙酰泽泻醇B通过激活SIRT1-LXRα通路对ox-LDL诱导大鼠VSMCs表型转化和迁移的影响

Effects of alisol B 23-acetate on ox-LDL-induced phenotypic transformation and migration of rat vascular smooth muscle cells by activating SIRT1-LXRα pathway

目的:观察23-乙酰泽泻醇B通过激活沉默信息调节因子1-肝X受体α(SIRT1-LXRα)通路抑制氧化型低密度脂蛋白(ox-LDL)诱导大鼠血管平滑肌细胞(VSMCs)表型转化及迁移的作用机制。方法:通过免疫细胞化学染色观察VSMCs收缩表型标记蛋白SM22α的变化,划痕实验测定VSMCs迁移及Western Blot检测VSMCs SIRT1、LXRα、MMP-9和MMP-2蛋白表达的变化。结果:在ox-LDL诱导下,SM22α蛋白表达显著降低(P<0.05),VSMCs向合成型转化,同时促进VSMCs的迁移(P<0.01),伴随着MMP-9和MMP-2蛋白表达显著上调(P<0.05,P<0.01),而显著抑制SIRT1、LXRα蛋白表达(P<0.01,P<0.05)。联合23-乙酰泽泻醇B干预后,SM22α蛋白表达显著增加(P<0.05),细胞向收缩表型转化,伴随SIRT1、LXRα蛋白表达显著提高(P<0.05,P<0.01),同时可显著抑制ox-LDL诱导VSMCs的迁移及MMP-9、MMP-2蛋白表达量(P<0.05,P<0.01)。结论:23-乙酰泽泻醇B能有效抑制VSMCs表型转换和迁移,其机制可能与激活SIRT1-LXRα通路有关。

Objective:To evaluate the inhibition of alisol B 23-acetate on oxidized low-density lipoprotein(Ox-LDL)-induced phenotypic transformation and migration of rat vascular smooth muscle cells(VSMCs) through activating SIRT1-LXRα pathway,and to explore the underlying mechanisms.Methods:The expression of VSMCs phenotypic marker SM22αwas determined using immunocytochemistry,and the migration of VSMCs was detected using a scratch-wound healing assay.The protein expression of Sirtuin(SIRT) 1,Liver X receptor-α(LXRα) and matrix metalloproteinase(MMP)-9,MMP-2 was determined by Western Blot.Results:Ox-LDL treatment caused a reduction in SM22α expression(P<0.05),VSMCs transformation to the synthetic phenotype,the extension of VSMCs migration distance(P<0.01) and the upregulation of MMP-9 and MMP-2 expression(P<0.05,P<0.01),inhibited SIRT1 and LXRα synthesis(P<0.05,P<0.01),while the addition of alisol B 23-acetate resulted in the significant elevation of SM22α expression(P<0.05),VSMCs transformation to the contractile phenotype,the shortening of cell migration distance and a reduction in MMP-9 and MMP-2 expression(P<0.05,P<0.01),increased SIRT1 and LXRα expression(P<0.05,P<0.01).Conclusion:The results of this study demonstrate that alisol B 23-acetate effectively reverses the phenotypic transformation and inhibits the migration of VSMCs,which may be associated with the activation of the SIRT1-LXRα signaling pathway.