Effect of mechanical stress on stemness of embryonic stem cells

已报道机械应变影响许多细胞类型的增殖/分化。然而，机械转导对胚胎干细胞（ES）的影响仍然未知。为了研究机械应变对ES细胞命运的影响，我们检测了单轴循环拉伸过程中Nanog的表达以及Nanog相关的细胞内信号传导。将小鼠ES细胞铺在弹性膜上，并在0.16 Hz下施加10%应变。在ES细胞分化过程中，Nanog的表达减少，以响应白血病抑制因子（LIF）的退出;然而，两天的机械应变减弱了Nanog表达的减少。另一方面，机械应力促进了Nanog转录上游的PI 3 K-Akt信号通路，提示机械应力可能通过肌动蛋白-PI 3 K-Akt信号通路调控ES细胞中Nanog的表达。

Mechanical strain has been reported to affect the proliferation/differentiation of many cell types. however, the effects of mechanotransduction on embryonic stem (ES) cells remains unknown. To investigate the effects of mechanical strain on ES cell fate, we examined the expression of Nanog as well as Nanog-associated intracellular signaling during uniaxial cyclic stretch. The mouse ES cell was plated onto elastic membranes, and we applied 10% strain at 0.16 Hz. The expression of Nanog was reduced during ES cell differentiation in response to the withdrawal of leukemia inhibitory factor (LIF); however, two days of mechanical strain attenuated this reduction of Nanog expression. On the other hand, the mechanical strain promoted PI3K-Akt signaling, which is reported as an upstream of Nanog transcription.These findings imply that mechanical force plays a role in regulating Nanog expression in ES cells through the actin cytoskeleton-PI3K-Akt signaling.