Fig. 4.

Inhibitory effect of EuO on protein expressions and transcriptions of caspases 3, 6, 7, and 9 in H₂O₂-induced MC3T3-E1 cells

(a) Western blotting results and relative ratio of protein levels. The molecular weights detected for caspases 3, 6, 7, and 9 were 17, 34, 35, and 32 kDa, respectively; (b) RT-PCR results and relative ratio of protein levels. The fragments detected for caspases 3, 6, 7, and 9 and β-actin were 136, 132, 122, 425, and 348 bp, respectively. EuO significantly decreased the protein expressions of caspases 3, 6, 7, and 9 in H₂O₂ (800 µmol/L)-induced MC3T3-E1 cells, and the inhibition effect was positively correlated with the concentration of EuO. Group A: control; Group B: H₂O₂ at 800 µmol/L; Groups C–G: H₂O₂ at 800 µmol/L and EuO at 6.25, 12.5, 25, 50, and 100 µg/ml, respectively. Data are expressed as mean±SD. ^* P<0.05, compared with the control (H₂O₂- and EuO-free); ^▲ P<0.05, compared with H₂O₂ treatment alone