title: Metabolism of high density lipoprotein apolipoprotein A-I and cholesteryl ester in insulin resistant dog: a stable isotope study.
abstract: OBJECTIVE
  In reverse cholesterol transport (RCT), hepatic Scavenger Receptor class B type I (SR-BI) plays an important role by mediating the selective uptake of high-density lipoprotein cholesteryl ester (HDL-CE). However, little is known about this antiatherogenic mechanism in insulin resistance. HDL-CE selective uptake represents the main process for HDL-CE turnover in dog, a species lacking cholesteryl ester transfer protein activity. We therefore investigate the effects of diet induced insulin resistance on RCT.
  
  
  METHODS
  Five beagle dogs, in healthy and insulin resistant states, underwent a primed constant infusion of [1,2(13)C(2)]acetate and [5,5,5-(2)H(3)]leucine, as labelled precursors of CE and apolipoprotein (apo) A-I, respectively. Data were analysed using modelling methods.
  
  
  RESULTS
  HDL-apo A-I concentration did not change in insulin resistant state but apo A-I absolute production rate (APR) and fractional catabolic rate (FCR) were both higher (2.2- and 2.4-fold, respectively, p < 0.05). HDL-CE levels were lower (1.2-fold, p < 0.05). HDL-CE APR and FCR were both lower (2.3- and 2-fold, respectively, p < 0.05), as well as selective uptake (2.6-fold, p < 0.05).
  
  
  CONCLUSIONS
  Lower HDL-CE selective uptake suggests that RCT is impaired in obese insulin resistant dog.
authors.forename: F
authors.initials: F
authors.lastname: Briand
authors.forename: E
authors.initials: E
authors.lastname: Bailhache
authors.forename: P
authors.initials: P
authors.lastname: Nguyen
authors.forename: M
authors.initials: M
authors.lastname: Krempf
authors.forename: T
authors.initials: T
authors.lastname: Magot
authors.forename: K
authors.initials: K
authors.lastname: Ouguerram
mesh_terms: D000818:Animals; D016632:Apolipoprotein A-I / Q000097:blood*; D001692:Biological Transport; D002788:Cholesterol Esters / Q000097:blood*; D004285:Dogs; D007333:Insulin Resistance; D008297:Male; D009765:Obesity / Q000097:blood*
chemical_list: D016632:Apolipoprotein A-I; D002788:Cholesterol Esters