The effects of Zanthoxylum bungeanum extract on lipid metabolism induced by sterols.

Variant pharmacological activities of Zanthoxylum bungeanum were determined before. The aim of this study was to assess whether Z. bungeanum could regulate lipid metabolism. The cholesterol overloading HepG2 cells induced by sterols were used as in vitro model to study lipid-lowering activities of the n-butanol (BuOH) fraction isolated from Z. bungeanum (ZBBu). Male apolipoprotein E knockout (apoE-KO) mice with high fat diet were used as in vivo model. We firstly demonstrated ZBBu had effects on reversed lipid accumulation, decreased apoB and enhanced apoA1 secretion. It increased the amount of low density lipoprotein receptor (LDLR) protein, also significantly inhibited the expression of SREBP-1 and SREBP-2's target molecule (hydroxy methylglutaryl coenzyme A reductase, HMGCR), which might be active in stimulation of RCT. And the expression of genes involved in RCT, such as CYP27A1, LXR-α, ABCG1, was promoted by ZBBu. Furthermore, ZBBu could reduce serum TC, TG levels in apoE-KO mice. Our study indicated that ZBBu could regulate the lipid metabolism through increasing the amount of low density lipoprotein receptor (LDLR) and inducing the expression of genes involved in RCT.