Background: Intimal hyperplasia is a major complication of restenosis after angioplasty. The abnormal proliferation and oxidative stress of vascular smooth muscle cells (VSMCs) are the basic pathological feature of neointimal hyperplasia. 17β-Estradiol can inhibit VSMCs proliferation and inflammation. However, it is still unclear whether and how 17β-Estradiol affects intimal hyperplasia.
Methods: The neointima hyperplasia was observed by hematoxylin/eosin staining. The expression of PCNA, cyclin D1, NOX1, NOX4 and p47phox in neointima hyperplasia tissues and VSMCs was determined by qRT-PCR and Western blotting. MTS assay, cell counting and EdU staining were performed to detect cells proliferation. The oxidative stress was assessed by ROS staining.
Results: 17β-Estradiol suppressed carotid artery ligation-induced intimal hyperplasia, which is accompanied by an increase of BHLHE40 level. Furthermore, loss- and gain-of-function experiments revealed that BHLHE40 knockdown promotes, whereas BHLHE40 overexpression inhibits TNF-α-induced VSMC proliferation and oxidative stress. 17β-Estradiol inhibited TNF-α-induced VSMC proliferation and oxidative stress by promoting BHLHE40 expression, thereby suppressing MAPK signaling pathways. In addition, enforcing the expression of BHLHE40 leads to amelioration of intimal hyperplasia.
Conclusions: Our study demonstrates that 17β-Estradiol inhibits proliferation and oxidative stress in vivo and in vitro by promotion of BHLHE40 expression.
中文翻译:
17β-雌二醇通过上调 BHLHE40 表达抑制血管平滑肌细胞的增殖和氧化应激
背景:内膜增生是血管成形术后再狭窄的主要并发症。血管平滑肌细胞(VSMCs)的异常增殖和氧化应激是新生内膜增生的基本病理特征。17β-雌二醇可抑制VSMCs增殖和炎症。然而,17β-雌二醇是否以及如何影响内膜增生仍不清楚。
方法:通过苏木精/伊红染色观察到新生内膜增生。通过qRT-PCR和Western印迹测定新内膜增生组织和VSMC中PCNA、细胞周期蛋白D1、NOX1、NOX4和p47 phox的表达。进行MTS测定、细胞计数和EdU染色以检测细胞增殖。通过ROS染色评估氧化应激。
结果:17β-雌二醇抑制颈动脉结扎诱导的内膜增生,伴随着 BHLHE40 水平的增加。此外,功能丧失和功能获得实验表明 BHLHE40 敲低促进,而 BHLHE40 过表达抑制 TNF-α 诱导的 VSMC 增殖和氧化应激。17β-雌二醇通过促进 BHLHE40 表达抑制 TNF-α 诱导的 VSMC 增殖和氧化应激,从而抑制 MAPK 信号通路。此外,加强 BHLHE40 的表达导致内膜增生的改善。
结论: 我们的研究表明 17β-雌二醇抑制增殖和氧化应激 体内 和 体外 通过促进 BHLHE40 表达。