成纤维细胞生长因子2通过抑制TET2/UQCRH表达拮抗血管平滑肌细胞凋亡和促进其增殖

Fibroblast growth factor-2 inhibits vascular smooth muscle cell apoptosis and promotes its proliferation by suppressing the TET2/UQCRH expression

[目的]探讨10-11转位蛋白2(TET2)/泛醌细胞色素C还原酶铰链蛋白(UQCRH)轴在成纤维细胞生长因子2(FGF-2)抑制血管平滑肌细胞(VSMC)凋亡中的作用。[方法]正常培养的VSMC分为对照组、FGF-2组、FGF-2+成纤维细胞生长因子受体(FGFR)泛抑制剂LY2874455组。TET2基因过表达(OETET2)或UQCRH基因过表达(OEUQCRH)的VSMC分为对照组、FGF-2组、OETET2+FGF-2组或OEUQCRH+FGF-2组。采用Hoechst33342和PI染色检测细胞凋亡,CCK-8实验检测细胞增殖,Western blot检测凋亡相关蛋白pro-Caspase-3、cleaved Caspase-3、Bax、Bcl-2及TET2、UQCRH表达水平。运用NCBI、methprimer网站预测分析UQCRH基因启动子CpG岛位点。[结果]FGF-2可抑制VSMC凋亡、促进其增殖,下调促凋亡相关蛋白cleaved Caspase-3、Bax和TET2、UQCRH表达,上调抗凋亡蛋白Bcl-2表达(与对照组相比,P<0.05),但不影响pro-Caspase-3表达(与对照组相比,P>0.05),LY2874455可对抗FGF-2的作用(与FGF-2组相比,P<0.05)。TET2或UQCRH过表达可逆转FGF-2对VSMC抗凋亡、促增殖的作用,促进促凋亡相关蛋白表达上调,抗凋亡蛋白表达下调(与FGF-2组相比,P<0.05)。UQCRH基因启动子区域存在3个CpG岛。过表达TET2能上调FGF-2处理的VSMC中UQCRH表达(与FGF-2组相比,P<0.05)。[结论]FGF-2通过抑制TET2和UQCRH表达,减少VSMC凋亡,促进其增殖。

Aim To explore the role of the ten-eleven translocation 2(TET2)/ubiquinol-cytochrome C reductase hinge protein(UQCRH)axis in the inhibition of vascular smooth muscle cell(VSMC)apoptosis by fibroblast growth factor-2(FGF-2).Methods Cultured VSMCs were divided into control group,FGF-2 group,and FGF-2+fibroblast growth factor receptor(FGFR)pan-inhibitor LY2874455 group.VSMCs overexpressing TET2(OETET2)or UQCRH(OEUQCRH)were divided into control group,FGF-2 group,and OETET2+FGF-2 or OEUQCRH+FGF-2 group.Hoechst33342 and PI staining were used to detect cell apoptosis,CCK-8 assay was employed to measure cell proliferation,and Western blot was used to examine the expression levels of apoptosis-related proteins pro-Caspase-3,cleaved Caspase-3,Bax,Bcl-2,as well as TET2 and UQCRH.The NCBI and methprimer websites were utilized for predicting and analyzing CpG island sites in the UQCRH gene promoter.Results FGF-2 could inhibit VSMC apoptosis,promote proliferation,downregulate apoptosis-related proteins cleaved Caspase-3,Bax,TET2,and UQCRH expression,and upregulate anti-apoptotic protein Bcl-2 expression(compared with control group,P<0.05).However,it did not affect pro-Caspase-3 expression(compared with control group,P>0.05).LY2874455 could counteract the effects of FGF-2(compared with FGF-2 group,P<0.05).Overexpression of TET2 or UQCRH could reverse the anti-apoptotic and pro-proliferative effects of FGF-2 on VSMC,with upregulation of apoptosis-related protein expression and downregulation of anti-apoptotic protein expression(compared with FGF-2 group,P<0.05).The UQCRH gene promoter region contained three CpG islands.Overexpression of TET2 could upregulate UQCRH expression in VSMC treated with FGF-2(compared with FGF-2 group,P<0.05).Conclusion FGF-2,by inhibiting TET2 expression and UQCRH expression,reduces VSMC apoptosis and promotes its proliferation.