Mechanical stretching induces fibroblasts apoptosis through activating Piezo1 and then destroying actin cytoskeleton

The anatomical positions of pelvic floor organs are maintained by ligaments and muscles. Stress urinary incontinence (SUI) occurs when the pelvic floor tissues are repeatedly stimulated by excessive mechanical tension that exceeds the bearing capacity of ligaments or muscles. Besides, cells respond mechanically to mechanical stimulation by reconstituting the Piezo1 and cytoskeletal system. The aim of this study is to determine how Piezo1 and actin cytoskeleton are involved in the mechanized stretch (MS) induced apoptosis of human anterior vaginal wall fibroblasts (hAVWFs) and the mechanism. A four-point bending device was used to provide mechanical stretching to establish a cellular mechanical damage model. The apoptosis of hAVWFs cells in non-SUI patients was significantly increased by MS, which exhibited apoptosis rates comparable to those of SUI patients. Based on these findings, Piezo1 connects the actin cytoskeleton to the apoptosis of hAVWFs cells, providing an idea for the clinical diagnosis and treatment of SUI. However, the disassembly of the actin cytoskeleton suppressed the protective effect of Piezo1 silencing on MS. Based on these findings, Piezo1 connects the actin cytoskeleton to apoptosis of hAVWFs, providing new insight for the clinical diagnosis and treatment of SUI.