ABSTRACT
Objective To investigate the effects of berberine on cholesterol efflux in THP-1 macrophage derived foam cells, and explore the possible mechanism. Methods HP-1 cells were induced into macrophages by phorbol myristate acetate (PMA), and were treated with acetylated low-density lipoprotein (Ac-LDL) to establish the THP-1 macrophage derived foam cell models. Foam cells were divided into blank control group and berberine (5 to 20 μmol/L) treatment groups according to the way of treatment and berberine concentrations. After treatment for 24 h, flow cytometry was employed to detect AcLDL aggregation, enzymic method was adopted to detect contents of cholesterol and triglyceride, scintillation counting technique was used to detect cholesterol efflux, and effects of peroxisome proliferator-activated receptor-γ (PPARγ) antagonist GW9662 pretreatment on cholesterol efflux (pioglitazone as positive control) were analysed. Besides, RT-PCR was applied to detect expression of liver X receptor α (LXRα) and ATP binding cassette transporter A1 (ABCA1) mRNA. ResultsCompared with blank control group, AcLDL aggregation and contents of cholesterol and triglyceride of foam cells in various berberine treatment groups decreased significantly (P＜0.01), while cholesterol efflux increased (P＜0.01) in a dose-dependent manner. After GW9662 pretreatment, there was no significant difference in cholesterol efflux between various berberine treatment groups and control group (P>0.05). Furthermore, expression of LXRα and ABCA1 mRNA of foam cells in various berberine treatment groups was higher than that in blank control group. Conclusion Berberine may increase cholesterol efflux in THP-1 macrophage derived foam cells, the mechanism of which may be associated with activation of PPARγ pathway and increase of expression of LXRα and ABCA1 mRNA.