ABSTRACT
Objective::To clarify the inhibitory effect of essential oil from Alpinia zerumbet rhizome (EOFAZ) on oxidized low-density lipoprotein (ox-LDL)-induced transformation of macrophage into foam cell and explore its possible mechanism. Method::THP-1 monocyte was incubated with 100 μg·L-1 phorbol myristate acetate (PMA) to grow into macrophage, experiment was divided into 4 groups as follows, control group, model group (80 mg·L-1 ox-LDL), EOFAZ at low dose (80 mg·L-1 ox-LDL+ 4 μg·L-1 EOFAZ)and EOFAZ at high dose (80 g·L-1 ox-LDL+ 20 μg·L-1 EOFAZ). Mathye thiazolye telrazliurn (MTT) method was employed to examine the influence of EOFAZ on macrophage viability. Western blot was used to analyze the expression level of cluster of differentiation 36(CD36) and ATP-binding cassette transporter A1(ABCA1) protein in macrophage. Enzyme-linked immunosorbent assay (ELISA) was used to detect cholesteryl ester contents in macrophage. Oil red O staining was applied to determine the accumulation of lipids in macrophage. Result::EOFAZ showed non-toxic effect on macrophage. Compared to control group, macrophage in model group displayed higher level of cholesteryl ester and lipid droplet(P<0.01), as well as significant increasing of CD36 expression (P<0.01), but no effect on ABCA1 expression. EOFAZ notably reduced the contents of lipids and cholesteryl ester(P<0.01), down-regulated expression of CD36 and up-regulated expression of ABCA1 in macrophage in comparison with the model group(P<0.01), indicating that EOFAZ inhibited transformation of macrophage into foam cell. Conclusion::EOFAZ could inhibit ox-LDL-induced transformation of macrophage into foam cell, the underlying mechanism may involves its ability to increase CD36 expression and decrease ABCA1 expression in macrophage.