Osteopontin regulates the proliferation of rat aortic smooth muscle cells in response to gingipains treatment.

OBJECTIVE: The present study aimed to explore the possible effects of osteopontin (OPN) in the proliferation of rat aortic smooth muscle cells (RASMCs) stimulated by gingipains. METHODS: The proliferation of RASMCs in response to active gingipains treatment was evaluated by CCK-8 assay. OPN siRNA was designed, constructed and transfected into RASMCs at different concentrations. The cell cycle of RASMCs was analyzed by flow cytometry. OPN, α-SMA and calponin expression were examined by real-time PCR and western blot analysis. RESULTS: Gingipains promoted the proliferation of RASMCs and OPN expression. With siRNA-mediated OPN expression knockdown, the cell cycle of RASMCs was blocked in the G0/G1 phase. Furthermore, the expression of specific differentiation markers, α-SMA and calponin, also decreased. CONCLUSIONS: These results demonstrate that OPN has an impact on the proliferation and differentiation of RASMCs stimulated by gingipains.