Hyperhomocysteinemia induces vascular calcification by activating the transcription factor RUNX2 via Kr?ppel-like factor 4 up-regulation in mice
Hyperhomocysteinemia induces vascular calcification by activating the transcription factor RUNX2 via Kr?ppel-like factor 4 up-regulation in mice
复制标题
高同型半胱氨酸血症通过 Kr?ppel 样因子 4 上调激活转录因子 RUNX2 诱导小鼠血管钙化
DOI：
10.1074/jbc.ra119.009758
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发表时间：
2019
影响因子：
4.8
通讯作者：
Jia Shaobin
中科院分区：
文献类型：
--
作者：
Zhu Lili;Zhang Na;Yan Ru;Yang Wenjuan;Cong Guangzhi;Yan Ning;Ma Wanrui;Hou Jianjun;Yang Libo;Jia Shaobin
动脉粥样硬化的主要特征之一是血管钙化，这与不良心血管事件有关。同型半胱氨酸（Hcy）增加是高同型半胱氨酸血症的一个特征，与晚期血管钙化和血管平滑肌细胞（VSMC）的表型转换相关。氧化应激和高磷酸盐水平也会诱导 VSMC 钙化，表明 Krüppel 样因子 4 (KLF4) 信号通路也可能导致血管钙化。在本研究中，我们研究了这种可能性以及Hcy在血管钙化中的作用和机制。我们发现，在动脉粥样硬化载脂蛋白 E 缺陷 (ApoE−/−) 小鼠中，Hcy 显着增加体内血管钙化以及体外 VSMC 钙化。值得注意的是，Hcy 诱导的 VSMC 钙化与 KLF4 水平升高相关。 Hcy在体内钙化动脉粥样硬化病变和体外钙化VSMC中促进KLF4表达。 shRNA 介导的 KLF4 敲低阻断了 Hcy 诱导的 runt 相关转录因子 2 (RUNX2) 和 VSMC 钙化的上调。 RUNX2 抑制消除了 Hcy 诱导的 VSMC 钙化。使用 ChIP 分析，我们证明 KLF4 与 RUNX2 相互作用，这是 Hcy 刺激促进的相互作用。我们的实验还表明，KLF4 敲低减弱了 Hcy 诱导的 RUNX2 反式活性，表明 KLF4 在调节 RUNX2 反式活性中很重要。这些发现支持 Hcy 通过 KLF4-RUNX2 相互作用调节血管钙化的作用，并表明 Hcy 诱导的增强的 RUNX2 反式活性会增加 VSMC 钙化。这些见解揭示了开发预防或控制血管钙化的干预措施的可能机会。
One of the main characteristics of atherosclerosis is vascular calcification, which is linked to adverse cardiovascular events. Increased homocysteine (Hcy), a feature of hyperhomocysteinemia, is correlated with advanced vascular calcification and phenotypic switching of vascular smooth muscle cells (VSMCs). Oxidative stress and high phosphate levels also induce VSMC calcification, suggesting that the Krüppel-like factor 4 (KLF4) signaling pathway may also contribute to vascular calcification. In this study, we investigated this possibility and the role and mechanisms of Hcy in vascular calcification. We found that in atherosclerotic apolipoprotein E–deficient (ApoE−/−) mice, Hcy significantly increases vascular calcificationin vivo, as well as VSMC calcificationin vitro. Of note, the Hcy-induced VSMC calcification was correlated with elevated KLF4 levels. Hcy promoted KLF4 expression in calcified atherosclerotic lesionsin vivoand in calcified VSMCsin vitro. shRNA-mediated KLF4 knockdown blocked the Hcy-induced up-regulation of runt-related transcription factor 2 (RUNX2) and VSMC calcification. RUNX2 inhibition abolished Hcy-induced VSMC calcification. Using ChIP analysis, we demonstrate that KLF4 interacts with RUNX2, an interaction promoted by Hcy stimulation. Our experiments also revealed that the KLF4 knockdown attenuates Hcy-induced RUNX2 transactivity, indicating that KLF4 is important in modulating RUNX2 transactivity. These findings support a role for Hcy in regulating vascular calcification through a KLF4–RUNX2 interaction and indicate that Hcy-induced, enhanced RUNX2 transactivity increases VSMC calcification. These insights reveal possible opportunities for developing interventions that prevent or manage vascular calcification.