title: Quercetin improves macrophage reverse cholesterol transport in apolipoprotein E-deficient mice fed a high-fat diet.
abstract: BACKGROUND
  Quercetin, one of the most widely distributed flavonoids in plants, has been demonstrated to reduce hyperlipidaemia and atherosclerotic lesion formation. Reverse cholesterol transport (RCT) plays a crucial role in exporting cholesterol from peripheral cells, which is one mechanism utilized in the prevention and treatment of atherosclerosis. The aim of this study is to investigate whether quercetin reduces lipid accumulation by improving RCT in vivo.
  
  
  METHODS
  Apolipoprotein E-deficient mice fed a high-fat diet were used to investigate the effect of quercetin on RCT by an isotope tracing method, and the underlying mechanisms were clarified by molecular techniques.
  
  
  RESULTS
  These novel results demonstrated that quercetin significantly improved [3H]-cholesterol transfer from [3H]-cholesterol-loaded macrophages to the plasma (approximately 34% increase), liver (30% increase), and bile (50% increase) and finally to the feces (approximately 40% increase) for excretion in apolipoprotein E-deficient mice fed a high-fat diet. Furthermore, quercetin markedly increased the cholesterol accepting ability of plasma and high-density lipoprotein (HDL) and dramatically decreased the content of malondialdehyde in plasma and oxidized phosphocholine carried by HDL. Therefore, the underlying mechanisms of quercetin in improving RCT may be partially due to the elevated cholesterol accepting ability of HDL, the increased expression levels of proteins related to RCT, such as ATP-binding cassettes (ABC) A1 and G1, and the improved antioxidant activity ﻿of HDL﻿.
  
  
  CONCLUSIONS
  Quercetin accelerates RCT in an atherosclerosis model, which is helpful in clarifying the lipid-lowering effect of quercetin.
authors.affiliation: Key Laboratory of Atherosclerosis in Universities of Shandong Province, Institute of Atherosclerosis, Taishan Medical University, 2# Yingsheng East Road, Taian, Shandong Province, 271000, China.
authors.forename: Yingjie
authors.initials: Y
authors.lastname: Cui
authors.affiliation: Key Laboratory of Atherosclerosis in Universities of Shandong Province, Institute of Atherosclerosis, Taishan Medical University, 2# Yingsheng East Road, Taian, Shandong Province, 271000, China.|Research Center on Life Sciences and Environmental Sciences, Harbin University of Commerce, Harbin, 150076, China.
authors.forename: Pengbo
authors.initials: P
authors.lastname: Hou
authors.affiliation: Department of Chemistry and Chemical Engineering, Weifang University, Weifang, 261061, China.
authors.forename: Fahui
authors.initials: F
authors.lastname: Li
authors.affiliation: Affiliated Hospital of Taishan Medical University, Taian, 271000, China.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Key Laboratory of Atherosclerosis in Universities of Shandong Province, Institute of Atherosclerosis, Taishan Medical University, 2# Yingsheng East Road, Taian, Shandong Province, 271000, China. shucunqin@hotmail.com.
authors.forename: Shucun
authors.initials: S
authors.lastname: Qin
authors.affiliation: Key Laboratory of Atherosclerosis in Universities of Shandong Province, Institute of Atherosclerosis, Taishan Medical University, 2# Yingsheng East Road, Taian, Shandong Province, 271000, China.
authors.forename: Guanghai
authors.initials: G
authors.lastname: Zhou
authors.affiliation: School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China.
authors.forename: Xuelian
authors.initials: X
authors.lastname: Xu
authors.affiliation: Key Laboratory of Atherosclerosis in Universities of Shandong Province, Institute of Atherosclerosis, Taishan Medical University, 2# Yingsheng East Road, Taian, Shandong Province, 271000, China.
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Si
authors.affiliation: Key Laboratory of Atherosclerosis in Universities of Shandong Province, Institute of Atherosclerosis, Taishan Medical University, 2# Yingsheng East Road, Taian, Shandong Province, 271000, China. SD-GUO@hotmail.com.
authors.forename: Shoudong
authors.initials: S
authors.lastname: Guo
mesh_terms: D064286:ATP Binding Cassette Transporter 1 / Q000378:metabolism; D000070998:ATP Binding Cassette Transporter, Subfamily G, Member 1 / Q000378:metabolism; D000818:Animals; D016632:Apolipoprotein A-I / Q000378:metabolism; D001057:Apolipoproteins E / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport / Q000187:drug effects; D002460:Cell Line; D002784:Cholesterol / Q000097:blood / Q000378:metabolism*; D059305:Diet, High-Fat / Q000009:adverse effects*; D008075:Lipoproteins, HDL / Q000378:metabolism; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008817:Mice, Mutant Strains; D011794:Quercetin / Q000494:pharmacology*
chemical_list: D064286:ATP Binding Cassette Transporter 1; D000070998:ATP Binding Cassette Transporter, Subfamily G, Member 1; D016632:Apolipoprotein A-I; D001057:Apolipoproteins E; D002784:Cholesterol; D008075:Lipoproteins, HDL; D011794:Quercetin; C577833:Abca1 protein, mouse; C487540:ABCG1 protein, mouse
keywords: Animal; Atherosclerosis; Cholesterol; Diet; LC-MS/MS; Medicine