LIPUS Promotes Endothelial Differentiation and Angiogenesis of Periodontal Ligament Stem Cells by Activating Piezo1

BACKGROUND AND OBJECTIVES: Low-intensity pulsed ultrasound (LIPUS) promotes differentiation and regulates biological functions of various stem cells, but its effect on the endothelial differentiation of periodontal ligament stem cells (PDLSCs) is unclear. This study investigated the effect of LIPUS on endothelial differentiation and angiogenesis in PDLSCs and the role of the mechanically sensitive ion channel Piezo1 in this process. METHODS AND RESULTS: PDLSCs obtained from healthy people were used for endothelial induction, and 10 μg/ml lipopolysaccharide (LPS) was used to simulate the inflammatory state. The induced cells were treated with LIPUS (50 mW/cm(2), 1.5 MHz) to study its effect on the endothelial differentiation of PDLSCs and the tube formation of differentiated cells. PCR, flow cytometry, immunofluorescence, and Matrigel tube formation assays were used to detect the differentiation and tube formation of PDLSCs. GsMTx4 was used to inhibit the expression of Piezo1, and the role of the Piezo1 pathway in the endothelial differentiation and microvascular formation of PDLSCs after LIPUS treatment was studied. The data showed that LIPUS increased endothelial differentiation and angiogenesis in PDLSCs under inflammatory or noninflammatory conditions. The use of an inhibitor weakened the effect of LIPUS. CONCLUSIONS: This study demonstrated that LIPUS can activate the expression of Piezo1 and promote the endothelial differentiation and microvascular formation of PDLSCs.