[Effect of lovastatin and rosiglitazone on cholesterol reverse transportation in foam cell]

This study was designed to explore the function of ATP binding cassette transporter 1 (ABCA1) and Apolipoprotein A-I (ApoA-I) in cholesterol reverse transportation (RCT), the influence of lovastatin and rosiglitazone on the concentration of cholesterol (CHO) in THP-1 (human monocytic leukemia cell line) derived foam cells.

LDL from healthy volunteers was obtained by density-gradient ultracentrifugation and was oxidized by incubation with Cu2+ and ox-LDL was identified.Macrophages were induced from THP-1 cell by phorbol ester (PMA). Models of foam cells were built by incubating macrophages with oxLDL. The effect of lovastatin and rosiglitazone on ABCA1 protein expression in THP-1 cell line derived macrophage were detected by western blot. Foam cells were divided into 9 groups: control, ApoA-I, lovastatin, rosiglitazone lovastatin+ApoA-I, rosiglitazone+ApoA-I, ABCA1 monoclonal antibody pretreatment+ApoA-I, ABCA1 monoclonal antibody pretreatment+lovastatin+ApoA-I, ABCA1 monoclonal antibody pretreatment+rosiglitazone+ApoA-I. The concentration of intracellular CHO in each group was detected by using cholesterol kit.

As compared with control group, there are no big differences of CHO concentration within the cell of group lovastatin, rosiglitazone, and each ABCA1 monoclonal antibody pretreatment group (P>0.05), but the CHO concentration within the cells of group ApoA-I, lovastatin+ApoA-I, rosiglitazone+ApoA-I decreased obviously as compared with the control (P<0.05), and CHO concentration in group rosiglitazone+ApoA-I have a further decrease than the former two groups (P<0.05).

CHO concentration can be decreased in foam cells by cooperation of ABCA1 and ApoA-I mediate cholesterol efflux. Rosiglitazone can enhance this procedure in THP-1 macrophages derived foam cells which means that they can promote ABCA1 mediated cholesterol reverse transportation through improve ABCA1 protein expression.