Expression of cyclophilin A in foaming of macrophages induced by silica / 中国职业医学

ABSTRACT

OBJECTIVE: To investigate the role of cyclophilin A in the foaming process of macrophages induced by free silica( SiO_2). METHODS: The human peripheral blood mononuclear cell THP-1 in the logarithmic growth phase was induced and differentiated into human macrophages with phorbol 12-myristate 13-acetate at 100 μg/L for 48 hours. The cells were divided into 4 groups. The cells in the blank control group were not treated. The cells in the oxidized low-density lipoprotein( ox-LDL) control group were treated with a final concentration of 50 mg/L ox-LDL. The cells of 50 mg/L SiO_2 group were treated with 50 mg/L of SiO_2 and ox-LDL. The cells of 100 mg/L SiO_2 group were treated with 100 mg/L of SiO_2 and 50 mg/L of ox-LDL. After treatment of cells for 48 h,cell viability was measured by MTS method. The lipid accumulation of cells was observed by oil red O staining and colorimetric method; the expression of cyclophilin A in cell supernatant was detected by enzyme-linked immunosorbent assay,and the expression of cyclophilin A in the cells was detected by Western blotting. RESULTS: The cell viability was the highest when the concentration of SiO_2 was 100 mg/L compared with the control and other four SiO_2groups( P < 0. 01). The cell foaming change in the 100 mg/L SiO_2 group observed by oil red O staining significantly increased compared with the blank control group. The expression of total cholesterol,free cholesterol increased in the ox-LDL control group,50 mg/L SiO_2 group and 100 mg/L SiO_2group( P <0. 05),and the cholesterol specific gravity increased( P < 0. 05) compared with the blank control group,meanwhile the expression of cyclophilin A in the cell supernatant increased( P < 0. 05),and the expression in the macrophages cells decreased( P < 0. 05). CONCLUSION: Cyclophilin A is involved in the foaming process of macrophages induced by SiO_2.