Molecular structures of berberine and its derivatives and their effects on EMMPRIN expression. (A) Molecular structures of berberine (BBR) and its derivatives, dihydroberberine (dhBBR), and 8,8-dimethyldi-hydroberberine (di-MeBBR). (B-D) The effects of BBR and its derivatives on EMMPRIN expression was monitored by measuring the induction of EMMPRIN via flow cytometry (B) and Western blotting (C, D). PMA-induced macrophages were treated with BBR or its derivatives for 1 h (macrophages), or pre-treated with BBR or its derivatives for 1 h prior to incubation with oxLDL (50 μg/mL) for 24 h (foam cells). The expression of EMMPRIN was detected by flow cytometric analysis. *P < 0.05 vs. BBR group. #P < 0.05 vs. untreated control group. thBBR: tetrahydroberberine.