BGI College, Zhengzhou University, No. 40 Daxue Road, Zhengzhou, 450007, China; Henan Institute of Medical and Pharmaceutical Science, Zhengzhou University, No. 40 Daxue Road, Zhengzhou, 450052, China.
School of Basic Medical Sciences, Zhengzhou University, No. 100 Science Avenue, Zhengzhou, 450001, China.
Biomed Pharmacother. 2020 Nov;131:110796. doi: 10.1016/j.biopha.2020.110796. Epub 2020 Sep 26.
The acoustic radiation forces produced by ultrasonic stimulation induce shear stress on objects in the acoustic field. Piezo1, a mechanosensitive ion channel protein that is expressed on the plasma membranes of vertebrate cells, can sense shear stress and transduce it into downstream signaling. In this study, we examined the sensitivity of Piezo1 to ultrasonic stimulation and assessed its downstream biological functions in human umbilical vein endothelial cells (HUVECs). Ultrasonic stimulation using a stimulation power of 0.2 W and a frequency of 1 MHz for 10 s did not induce cell damage. However, ultrasonic stimulation induced an influx of calcium ions, which increased with an increase in the stimulation duration. Knockdown of Piezo1 protein decreased the influx of calcium ions during ultrasonic stimulation, which demonstrated that Piezo1 may be activated by the shear stress produced by ultrasonic stimulation. The influx of calcium ions in response to ultrasonic stimulation could be modulated by the Piezo1 protein level. Additionally, ultrasonic stimulation reduced the levels of downstream factors such as MLCK and ATP, which are involved in the Ca/CaM/MLCK pathway, by suppressing Piezo1. As the Ca/CaM/MLCK pathway influences the permeability of the cell membrane, the internalization of FITC-Dextran into cells under ultrasonic stimulation was validated. Ultrasonic stimulation was demonstrated to promote the increase in cell permeability, and the suppression of Piezo1 was shown to induce the decrease in cell permeability. Therefore, this study shows that ultrasonic stimulation may modulate the permeability of the membrane of HUVECs by modulating the expression of Piezo1 protein.
超声刺激产生的声辐射力会在声场中对物体产生切向应力。Piezo1 是一种机械敏感的离子通道蛋白，表达于脊椎动物细胞的质膜上，能够感知切向应力并将其转导为下游信号。在本研究中，我们检测了 Piezo1 对超声刺激的敏感性，并评估了其在人脐静脉内皮细胞（HUVEC）中的下游生物学功能。使用 0.2 W 刺激功率和 1 MHz 频率的超声刺激 10 s 不会引起细胞损伤。然而，超声刺激诱导钙离子内流，且随着刺激持续时间的增加而增加。Piezo1 蛋白的敲低降低了超声刺激过程中的钙离子内流，表明 Piezo1 可能被超声刺激产生的切向应力激活。钙离子内流对超声刺激的反应可以通过 Piezo1 蛋白水平来调节。此外，超声刺激通过抑制 Piezo1 降低了下游因子如 MLCK 和 ATP 的水平，这些因子参与了 Ca/CaM/MLCK 通路。由于 Ca/CaM/MLCK 通路影响细胞膜的通透性，因此验证了在超声刺激下 FITC-Dextran 进入细胞的内化。超声刺激被证明可以促进细胞通透性的增加，而抑制 Piezo1 则诱导细胞通透性的降低。因此，本研究表明，超声刺激可能通过调节 Piezo1 蛋白的表达来调节 HUVEC 细胞膜的通透性。
