Fig. 3

Flow cytometric analysis of Ti particle-induced apoptosis in MLO-Y4 osteocytes by Annexin V/PI staining. Cells were treated with Ti particles (0 (control), 0.1 mg/mL, and 1.0 mg/mL) for 24 h (a) and 48 h (b), and stained with FITC-conjugated Annexin V. Apoptosis of cells was quantified by flow cytometry. Q4 represents apoptotic cells. c Data from (a) and (b) are as a percentage of apoptotic MLO-Y4 cells (mean ± SD). At 24 h, apoptosis rates of the cells exposed to 1.0 mg/mL Ti particles were higher than those of the control group and the 0.1 mg/mL group (* p < 0.05). At 48 h, rates of apoptosis were higher in cells exposed to 0.1 mg/mL or 1.0 mg/mL Ti particles than in the control group (* p < 0.05)