Osteopontin can decrease the expression of Col-II and COMP in cartilage cells in vitro.

OBJECTIVE To observe the effect of osteopontin (OPN) on the expression of collagen type II (Col-II) and oligomeric matrix protein COMP in cartilage cells of knee osteoarthritis, and explore the mechanism of OPN in the knee osteoarthritis. METHODS Cartilage cells were isolated from fetal rabbit, they were divided into 3 groups: A (control); B (0.5 μM OPN) and C (1 μM OPN). The expression levels of Col-2 and COMP were detected by RT-PCR and Western blotting methods. MMP-13 was detected using ELISA. The proliferation was determined by MTT method. RESULTS Compared with the group, the expression levels of Col-2 and COMP in cartilage cells decreased in the intervention group with dose dependent (P<0.05). The expression of MMP-13 in culture supernatant and the proliferation increased in the intervention group (P<0.05). CONCLUSION OPN can down-regulate the expression levels of Col-2 and COMP in cartilage cells and up-regulate the expression of MMP-13 in culture supernatant and promote the proliferation of cells, which could accelerate the pathological process of cartilage cells.