Regulation effect of quercetin on cholesterol influx and efflux from RAW264.7 macrophage / 国际药学研究杂志

ABSTRACT

Objective: To investigate the effects of quercetin on cholesterol accumulation and cholesterol flow in RAW264.7 macrophages and explore the potential mechanism underlying its anti-atherogenic activity. Methods: The inhibitory effect of quercetin on cholesterol accumulation induced by oxidized low-density lipoprotein (ox-LDL) was assessed by oil red O staining and total cholesterol (TC) specific kits in RAW264.7 macrophages. And the action of cholesterol efflux and influx was tested by fluorescent assays. Cholesterol flow-associated genes expression was detected by real-time quantitative PCR (RT-PCR). Results: Quercetin significantly inhibited the cholesterol accumulation. Treatment with quercetin (10 μmol/L) significantly enhanced cholesterol efflux and substantially inhibited cholesterol influx. RT-PCR showed that quercetin significantly increased the mRNA levels of peroxisome proliferator-activated receptor γ (PPARγ), liver X receptor alpha (LXRα), ATP-binding cassette, subfamily A1 (ABCA1) and subfamily G1 (ABCG1), decreased scavenger receptor (SR)-A1 and SR-A2. Conclusion: Quercetin might be a new inhibitor on intracellular cholesterol accumulation. Upregulation of the classical PPARγ-LXRα-ABCA1/ ABCG1 pathway and down-regulation of SR-A1 and SR-A2 may participate in its suppressive effect on intracellular cholesterol accumulation.