on March 15, 2007
Published online before print March 15, 2007, doi: 10.1161/ATVBAHA.106.136382
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Submitted on August 18, 2006
Accepted on March 4, 2007
In Vivo Evidence for a Role of Adipose Tissue SR-BI in the Nutritional and Hormonal Regulation of Adiposity and Cholesterol Homeostasis
Laurent Yvan-Charvet *;
From INSERM (L.Y-C., A.B., P.B., P.F., G.D., A.Q-B.), U671, Centre Biomédical des Cordeliers, Paris, France; Université Pierre et Marie Curie-Paris6 UMR-S 671, Paris, France; INSERM (X.R.), U505, Centre Biomédical des Cordeliers, Paris, France; CNRS UMR6543 (F.M., G.A., M.T.), Centre National de la Recherche Scientifique, Nice, France.
* To whom correspondence should be addressed. E-mail: ly2159{at}columbia.edu.
Objectives--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.
Methods and Results--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.
Conclusions--Our results raise the possibility that adipose tissue SR-BI translocation might be a link between adipose tissue lipid storage and HDL clearance.
Key words: adipose tissue • angiotensin II • high-density lipoprotein • insulin
This article has been cited by other articles:
 |
|
 |
|
  P. Rao, Z. H. Huang, and T. Mazzone Angiotensin II Regulates Adipocyte Apolipoprotein E Expression J. Clin. Endocrinol. Metab., November 1, 2007; 92(11): 4366 - 4372. [Abstract] [Full Text] [PDF]
|
|