Mechanism of Abnormal Chondrocyte Proliferation Induced by Piezo1-siRNA Exposed to Mechanical Stretch.

OBJECTIVE: To investigate the effect of small interfering RNA targeting mechanosensitive ion channel protein Piezo1 (Piezo1-siRNA) on abnormal chondrocyte proliferation exposed to mechanical stretch. METHODS: Construct and screen effective Piezo1-siRNA sequences and explore an appropriate method to transfect lentiviral vector into chondrocytes exposed to mechanical stretch. Western blot and RT-PCR were used to detect the mRNA and protein expression of Piezo1, Kif18A, and β-tubulin, respectively. Flow cytometry was used to measure the changes in the chondrocyte cycle. The proliferation of chondrocyte was evaluated by cell counting kit-8. RESULTS: According to the mRNA and protein expression of Piezo1, the effective siRNA sequence was successfully screened. Compared with the 0 h group, mechanical stretch upregulated the expression of Piezo1, Kif18A, and β-tubulin, resulting in chondrocyte cycle arrest and eventually inhibiting chondrocyte proliferation. Moreover, Piezo1-siRNA transfection effectively blocks this process and promotes the proliferation of chondrocyte. CONCLUSION: Piezo1-siRNA can reduce the inhibition of chondrocyte proliferation induced by mechanical stretch via downregulating the expression of Kif18A and inhibiting the depolymerization of microtubules. Piezo1-siRNA plays a protective role in chondrocytes, which provides a potential method for the treatment of OA under abnormal mechanical stimulation.