Hong-Brown Ly Q, Brown C Randell, Navaratnarajah Maithili, Lang Charles H
Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania, 17033, USA.
J Cell Biochem. 2015 Jan;116(1):91-101. doi: 10.1002/jcb.24945.
A variety of stressors including alcohol (EtOH) are known to induce collagen production and fibrotic diseases. Matrix metalloproteinases (MMP) play an important role in regulating fibrosis, but little is known regarding the relationship between EtOH and MMPs. In addition, the signaling cascades involved in this process have not been elucidated. We have identified the MMP Adamts1 as a target of EtOH regulation. To characterize the function of Adamts1, we examined EtOH-induced alterations in collagen I and elastin protein levels in C2C12 myocytes. Incubation of myocytes with 100 mM EtOH decreased elastin and increased collagen content, respectively, and these changes were associated with increased O-GLcNAc modification of Adamts1. Conversely, silencing of Adamts1 by siRNA blocked the adverse effects of EtOH on collagen and elastin levels. Similar results were obtained after treatment with a pharmacological inhibitor of MMP. Changes in collagen were due, at least in part, to a decreased interaction of Adamts1 with its endogenous inhibitor TIMP3. The AMPK inhibitor compound C blocked the EtOH-induced stimulation of collagen and O-GLcNAc Adamts1 protein. Changes in AMPK appear linked to FoxO1, since inhibition of FoxO1 blocked the effects of EtOH on AMPK phosphorylation and O-GLcNAc levels. These FoxO-dependent modifications were associated with an upregulation of the FoxO1 transcription target sestrin 3, as well as increased binding of sestrin 3 with AMPK. Collectively, these data indicate that EtOH regulates the collagen I and elastin content in an Adamts1-dependent manner in myocytes. Furthermore, Adamts1 appears to be controlled by the FoxO1-sestrin 3-AMPK signaling cascade.
包括酒精(EtOH)在内的多种应激源已知可诱导胶原蛋白生成和纤维化疾病。基质金属蛋白酶(MMP)在调节纤维化过程中起重要作用,但关于EtOH与MMP之间的关系知之甚少。此外,该过程中涉及的信号级联尚未阐明。我们已确定MMP Adamts1是EtOH调节的靶点。为了表征Adamts1的功能,我们检测了EtOH诱导的C2C12肌细胞中I型胶原蛋白和弹性蛋白水平的变化。用100 mM EtOH孵育肌细胞分别降低了弹性蛋白含量并增加了胶原蛋白含量,这些变化与Adamts1的O-GlcNAc修饰增加有关。相反,用siRNA沉默Adamts1可阻断EtOH对胶原蛋白和弹性蛋白水平的不良影响。用MMP的药理抑制剂处理后也获得了类似结果。胶原蛋白的变化至少部分归因于Adamts1与其内源性抑制剂TIMP3的相互作用减少。AMPK抑制剂化合物C阻断了EtOH诱导的胶原蛋白刺激和O-GlcNAc Adamts1蛋白。AMPK的变化似乎与FoxO1有关,因为抑制FoxO1可阻断EtOH对AMPK磷酸化和O-GlcNAc水平的影响。这些FoxO依赖性修饰与FoxO1转录靶点sestrin 3的上调以及sestrin 3与AMPK的结合增加有关。总体而言,这些数据表明EtOH以Adamts1依赖性方式调节肌细胞中的I型胶原蛋白和弹性蛋白含量。此外,Adamts1似乎受FoxO1-sestrin 3-AMPK信号级联控制。