Effect of KLF4 Overexpression on Cholesterol Accumulation and Expression of ABCA1 in RAW264.7

Objective To investigate cholesterol accumulation and expression of ATP binding cassette transporter A1(ABCA1) in RAW264.7 affected by Kruppel-like factor 4(KLF4).Methods Stable subline of RAW264.7 cells over-expressed KLF4 were established.RAW264.7cells were induced into foam cells by 30 μg/ml oxidized low density lipoprotein(ox-LDL)for 24 h.Lipid droplets in cytoplasm were observed by Red oil O staining.The cellular contents of total cholesterol(TC) and free cholesterol(FC) were examined by high performance liquid chromatography(HPLC).The protein expression of ABCA1 and KLF4 were detected by Western blot.Results In model group,Oil red O-staining showed cells were filled with lipid droplet and the expression of ABCA1 and KLF4 increased compared the control group.Compared with the model group,lipid droplets and the contents of FC and CE were decreased in the KLF4 over-expressed cell,and the protein expression of ABCA1 increased.Conclusion KLF4 could up-regulate the expression of ABCA1 and inhibit the lipid accumulation induced by ox-LDL in RAW 264.7 macrophage-derived foam cells.