angiotensinogen and cholesteryl-oleyl-ether

This study examines the role of insulin and angiotensin II in high-density lipoprotein (HDL) metabolism by focusing on the regulation and function of scavenger receptor type-BI (SR-BI) in adipose tissue.. Insulin or angiotensin II injection in wild-type mice induced a decrease in circulating HDL and it was associated with the translocation of SR-BI from intracellular sites to the plasma membrane of adipose tissue. Refeeding upregulated adipose HDL selective cholesteryl esters uptake and SR-BI proteins through transcriptional and posttranscriptional mechanisms. This occurred along with a decrease in serum HDL and an increase in adipose cholesterol content. Similar results were obtained with transgenic mice overexpressing locally angiotensinogen in adipose tissue. In adipose 3T3-L1 cell line, HDL induced lipogenesis by increasing liver X receptor binding activity. This mechanism was dependent of insulin and angiotensin II.. Our results raise the possibility that adipose tissue SR-BI translocation might be a link between adipose tissue lipid storage and HDL clearance.

Topics: 3T3-L1 Cells; Adipocytes; Adipose Tissue; Adiposity; Angiotensin II; Angiotensinogen; Animals; ATP Binding Cassette Transporter 1; ATP-Binding Cassette Transporters; Cell Membrane; Cholesterol; Cholesterol, HDL; DNA-Binding Proteins; Eating; Epididymis; Homeostasis; Insulin; Lipogenesis; Liver X Receptors; Male; Mice; Mice, Transgenic; Orphan Nuclear Receptors; Protein Transport; Receptors, Cytoplasmic and Nuclear; RNA, Messenger; Scavenger Receptors, Class B; Sterol Regulatory Element Binding Protein 1; Time Factors; Transcription, Genetic; Triglycerides