Tanshinone IIA affects the HDL subfractions distribution not serum lipid levels: Involving in intake and efflux of cholesterol

Abstract

Aim of study: Tanshinone IIA is an active component of the traditional Chinese medicine. This study aimed at investigating the mechanism of tanshinone IIA on anti-atherosclerosis, which may be because of that Tanshinone IIA can affect the HDL subfractions distribution and then regulate reverse cholesterol transport.

Materials and methods: A model of hyperlipidaemia in rats was used. Tanshinone IIA was given daily after hyperlipidaemia. In vivo, lipid deposition and morphological changes in liver were analyzed; HDL subfractions and lipid level in serum as well as in liver were measured; the expression of genes related to cholesterol intake in liver and peritoneal macrophage cholesterol efflux were evaluated. In vitro, HepG2 cells and THP-1 cells were pretreated with tanshinone IIA and subsequently with ox-LDL to evaluate the total cholesterol and the expression of related genes.

Results: Tanshinone IIA reduced the lipid deposition in liver. Moreover, it did not affect the serum lipid levels but reduced the levels of HDL middle subfractions and increased the levels of HDL large subfractions. Furthermore, tanshinone IIA could regulate the expressions of CYP7A1, LDL-R, SREBP2 and LCAT in the liver as well as the ABCA1 and CD36 in macrophage cells which is involving in the cholesterol intake and efflux respectively. It could reduce lipid accumulation caused by ox-LDL induction, and that also regulate the expressions of LDL-R, HMGCR and SREBP2 in HepG2 and ABCA1, CD36 in THP-1 cells.

Conclusion: A novel finding that tanshinone IIA was not reduce the serum lipid level but affects the HDL subfractions distribution and thereby regulating the intake and efflux of cholesterol.

Keywords: Efflux of cholesterol; HDL subfractions; Intake of cholesterol; SREBP-2; Tanshinone IIA.