title: New developments in selective cholesteryl ester uptake.
abstract: OBJECTIVE
  Selective lipid uptake (SLU) is known to be a major pathway of lipoprotein cholesterol metabolism in experimental animals and humans, but remains poorly understood. This review provides a brief overview of SLU mediated by the HDL receptor scavenger receptor B-type I (SR-BI), and highlights several surprising new findings related to the impact of SLU pathways in cholesterol homeostasis.
  
  
  RESULTS
  Under certain conditions, SR-BI-mediated SLU contributes to reverse cholesterol transport (RCT) independently of ABCG5/G8-mediated biliary cholesterol secretion, implying a novel trafficking mechanism. Hepatic SR-BI expression and RCT are decreased in diabetic mice. Farnesoid X receptor (FXR) and the microRNAs miR-185, miR-96 and miR-223 are emerging therapeutic targets for increasing SR-BI expression. SR-BI-independent selective cholesteryl ester uptake is a newly characterized pathway in macrophage foam cells.
  
  
  CONCLUSIONS
  New findings underscore the importance of SR-BI-mediated SLU in hepatic SLU and RCT, while indicating that further investigation is needed to define SLU pathways, including SR-BI-independent macrophage selective cholesteryl ester uptake. The intracellular trafficking of cholesterol in these pathways appears to be critical to their normal function and is a major subject of ongoing studies.
authors.affiliation: Department of Veterans Affairs Medical Center, Lexington, Kentucky, USA.
authors.forename: Jason M
authors.initials: JM
authors.lastname: Meyer
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Graf
authors.forename: Deneys R
authors.initials: DR
authors.lastname: van der Westhuyzen
mesh_terms: D000071018:ATP Binding Cassette Transporter, Subfamily G, Member 5; D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001693:Biological Transport, Active / Q000235:genetics; D002788:Cholesterol Esters / Q000235:genetics / Q000378:metabolism*; D003920:Diabetes Mellitus / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008074:Lipoproteins / Q000235:genetics / Q000378:metabolism; D008099:Liver / Q000378:metabolism* / Q000473:pathology; D008264:Macrophages / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics / Q000378:metabolism; D051122:Scavenger Receptors, Class B / Q000235:genetics / Q000378:metabolism*; D000099150:Receptor, Farnesoid X-Activated
chemical_list: D000071018:ATP Binding Cassette Transporter, Subfamily G, Member 5; D018528:ATP-Binding Cassette Transporters; D002788:Cholesterol Esters; D008074:Lipoproteins; D035683:MicroRNAs; D018160:Receptors, Cytoplasmic and Nuclear; D051122:Scavenger Receptors, Class B; D000099150:Receptor, Farnesoid X-Activated; C416945:ABCG5 protein, human; C462600:ABCG5 protein, mouse; C495124:SCARB1 protein, human; C454739:Scarb1 protein, mouse