Functional role of mechanosensitive ion channel Piezo1 in human periodontal ligament cells

Objective: To evaluate the function of Piezo1, an evolutionarily conserved mechanically activated channel, in periodontal ligament (PDL) tissue homeostasis under compressive loading. Materials and Methods: Primary human PDL cells (hPDLCs) were isolated, cultured, and then subjected to 2.0 g/cm(2) static compressive loading for 0.5, 3, 6, and 12 hours, respectively. The expressions of Piezo1 and osteoclastogenesis marker gene were assessed by semiquantitative reverse transcription-polynnerase chain reaction. In addition, Piezo1 inhibitor, GsMTx4, was used to block the function of Piezo1, and tumor necrosis factor-alpha was also used as a positive control. After 12 hours of compressive loading the PDLCs were co-cultured with murine nnonocytic cell line RAW264.7. immunofluorescence, western blot, enzyme-linked immunosorbent assay, and tartrate-resistant acid phosphatase staining were also used to test the potency of PDLCs to induce osteoclastogenesis and the activation of nuclear factor (NF)-kappa B. Results: Piezo1, cyclooxygenase-2, receptor activator of NF-kappa B ligand, and prostaglandin E2 were significantly upregulated under static compressive stimuli. GsMTx4 repressed osteoclastogenesis in the mechanical stress-pretreated PDLCs-RAW264.7 co-culture system. Furthermore, NF-kappa B signaling pathway was involved in the mechanical stress induced osteoclastogenesis. Conclusions: Piezo1 exerts a transduction role in mechanical stress induced osteoclastogenesis in hPDLCs.