SIRT1/DRP1在染料木素抑制氧化型低密度脂蛋白诱导的人脐静脉内皮细胞凋亡中的作用

The role of SIRT1/DRP1 in genistein suppressing ox-LDL-induced apoptosis of human umbilical vein endothelial cells

摘要:

目的]阐明沉默信息调节因子1(SIRT1)/线粒体动力相关蛋白1(DRP1)在染料木素抑制氧化型低密度脂蛋白(ox-LDL)诱导的内皮细胞凋亡中的作用。 [方法]体外培养人脐静脉内皮细胞(HUVEC),测定线粒体裂变因子(MFF)、线粒体分裂蛋白1(FIS1)、线粒体融合素1(MFN1)、线粒体融合素2(MFN2)和线粒体内膜视神经萎缩症蛋白1(OPA1),以及线粒体凋亡关键分子Bcl-2、Bax、细胞色素c(Cytc)、凋亡蛋白酶激活因子1(APAF1)、剪切的Caspase-9、剪切的Caspase-3、DRP1的乙酰化和磷酸化水平,以及DRP1和Bax的相互作用。 [结果]染料木素活化SIRT1,抑制DRP1乙酰化和磷酸化而抑制ox-LDL诱导的DRP1活性(均P＜0.05)；抑制MFF和FIS1,增加MFN1、MFN2和OPA1水平而抑制ox-LDL诱导的内皮细胞线粒体裂变(均P＜0.05)；抑制p-DRP1和Bax复合物形成,通过促进Bcl-2,抑制Bax、Cytc、APAF1、剪切的Caspase-9和剪切的Caspase-3水平而抑制ox-LDL诱导的内皮细胞凋亡(均P＜0.05)。 [结论]染料木素活化SIRT1抑制DRP1活性,通过抑制内皮细胞线粒体裂变而抑制ox-LDL诱导的内皮细胞凋亡。SIRT1/DRP1在染料木素抑制ox-LDL诱导的内皮细胞凋亡中发挥重要作用。

Abstract:

Aim To clarify the role of sirtuin 1(SIRT1)/dynamin-related protein 1(DRP1) in genistein inhibiting oxidized low density lipoprotein(ox-LDL)-induced apoptosis of human umbilical vein endothelial cells(HUVEC). Methods HUVECs were cultured in vitro. The levels of mitochondrial fission factor (MFF), mitochondrial fission protein 1 (FIS1), mitofusin 1 (MFN1), mitofusin 2 (MFN2), optic atrophy 1 (OPA1), Bcl-2, Bax, cytochrome c (Cyt c), apoptotic protease activating factor 1 (APAF1), cleaved Caspase-9, cleaved Caspase-3, p-DRP1(Ser616) and acetylation-DRP1 (ac-DRP1), as well as the interaction between p-DRP1 and Bax were examined. Results Compared with ox-LDL treatment, genistein pretreatment suppressed the activity of DRP1 through diminishing acetylation and phosphorylation, which was associated with activating SIRT1(all P＜0.05). Genistein pretreatment inhibited mitochondrial fission by enhancing MFN1, MFN2 and OPA1, and reducing MFF and FIS1(all P＜0.05). Genistein pretreatment suppressed apoptosis through inhibiting the interaction between p-DRP1 and Bax, accompanied with increasing Bcl-2 and decreasing Bax, Cyt c, APAF1, cleaved Caspase-9 and Caspase-3 (all P＜0.05). Conclusion Genistein suppressed ox-LDL-induced mitochondrial fission and apoptosis through activating SIRT1and inhibiting DRP1 in HUVEC.Therefore, SIRT1/DRP1 had a crucial role in genistein inhibiting ox-LDL-induced apoptosis in HUVEC.