Department of Chemistry and Biochemistry, São Paulo State University (UNESP), Institute of Biosciences, Botucatu, Brazil.
Electron Microscopy Center, São Paulo State University (UNESP), Institute of Biosciences, Botucatu, Brazil.
J Cell Physiol. 2019 Jul;234(7):11287-11303. doi: 10.1002/jcp.27787. Epub 2018 Nov 22.
Shear stress changes are associated with a repertory of signaling cascade modulating vascular phenotype. As shear stress-related tensional forces might be associated with pathophysiological susceptibility, a more comprehensive molecular map needs to be addressed. Thus, we subjected human umbilical vein endothelial cells (HUVECs) to a circuit of different tensional forces in vitro considering the following three groups: (a) physiological blood flow shear stress condition (named Normo), (b) a hypertensive blood flow shear stress (named Hyper), and (c) these hyper-stressed cells were returned to Normo condition (named Return). The samples were properly collected to allow different methodologies analysis. Our data showed a pivotal involvement of c-Src on driving the mechanotransduction cascade by modulating signaling related with adhesion, survival (PI3K/Akt) and proliferative phenotype. Moreover, c-Src seems to develop important role during extracellular matrix remodeling. Additionally, proteomic analysis showed strong involvement of heat shock protein 70 (HSP70) in the hypertensive-stressed cells; it being significantly decreased in return phenotype. This result prompted us to investigate 20S proteasome as an intracellular proteolytic alternative route to promote the turnover of those proteins. Surprisingly, our data reveled significant overexpression of sets of proteasome subunit α-type (PSMA) and β-type (PSMB) genes. In conjunction, our data showed c-Src as a pivotal protein to drive mechanotransduction in endothelial cells in a HSP70-dependent turnover scenario. Because shear patterns is associated with pathophysiological changes, such as atherosclerosis and hypertension, these results paved new road to understand the molecular mechanism on driving mechanotransduction in endothelial cells and, if drugable, these targets must be considered within pharmacological treatment optimization.
切应力变化与调节血管表型的信号级联反应库有关。由于与切应力相关的张应力可能与病理生理易感性有关，因此需要更全面的分子图谱。因此，我们在体外对人脐静脉内皮细胞（HUVEC）施加了不同的张应力循环，考虑了以下三组：（a）生理血流切应力条件（命名为Normo），（b）高血压血流切应力（命名为Hyper），和（c）将这些高应压力的细胞恢复到Normo 条件（命名为Return）。适当收集样本以允许进行不同的方法分析。我们的数据表明，c-Src 通过调节与粘附、存活（PI3K/Akt）和增殖表型相关的信号转导，在驱动机械转导级联中起着关键作用。此外，c-Src 在细胞外基质重塑过程中似乎起着重要作用。此外，蛋白质组学分析显示热休克蛋白 70（HSP70）在高血压应激细胞中强烈参与；在回归表型中显著减少。这一结果促使我们研究 20S 蛋白酶体作为一种细胞内蛋白水解替代途径，以促进这些蛋白质的周转。令人惊讶的是，我们的数据显示蛋白酶体亚基α型（PSMA）和β型（PSMB）的一组基因的过度表达。结合起来，我们的数据表明 c-Src 作为一种关键蛋白，在 HSP70 依赖的周转率场景中驱动内皮细胞中的机械转导。由于切应力模式与病理生理变化相关，如动脉粥样硬化和高血压，这些结果为理解驱动内皮细胞机械转导的分子机制开辟了新的道路，如果可以作为药物使用，这些靶点必须在药物治疗优化中考虑。
