Troglitazone metabolism and transporter effects in chimeric mice: a comparison between chimeric humanized and chimeric murinized FRG mice

Xenobiotica. 2014 Jan;44(2):186-95. doi: 10.3109/00498254.2013.879237. Epub 2014 Jan 13.


1. The biotransformation, hepatic transporter and blood chemistry effects of troglitazone were investigated following 7 days of dosing at 600 mg/kg/day to chimeric murinized or humanized FRG mice, Mo-FRG and Hu-FRG mice, respectively. 2. Clinical chemistry and histopathology analysis revealed a significant drop in humanization over the time course of the study for the Hu-FRG mice but no significant changes associated with troglitazone treatment in either the Mo-FRG or the Hu-FRG models. No changes in transporter expression in livers of these mice were observed. Oxidative and conjugative metabolic pathways were identified with a 15- to 18-fold increase in formation of troglitazone sulfate in the Hu-FRG mice compared with the Mo-FRG mice in blood and bile, respectively. This resembles the troglitazone metabolism in human and these data are comparable with the formation of this metabolite in the chimeric uPA(+/+)/SCID mice. 3. However, larger amounts of troglitazone glucuronide were also observed in the Hu-FRG mouse compared with the Mo-FRG mouse which may be an effect of the drop in humanization of the Hu-FRG mouse during the study. 4. Highly humanized mice have a considerable potential in providing a useful first insight into circulating human metabolites of candidate drugs metabolized in the liver.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bile / metabolism
  • Blood Chemical Analysis
  • Chromans / metabolism*
  • Chromans / pharmacokinetics*
  • Hepatocytes / transplantation
  • Humans
  • Hydrolases / genetics
  • Inactivation, Metabolic
  • Liver / drug effects
  • Liver / metabolism*
  • Male
  • Membrane Transport Proteins / metabolism*
  • Mice
  • Mice, Transgenic
  • Sulfuric Acid Esters / metabolism
  • Thiazolidinediones / metabolism*
  • Thiazolidinediones / pharmacokinetics*
  • Transplantation Chimera
  • Troglitazone


  • Chromans
  • Membrane Transport Proteins
  • Sulfuric Acid Esters
  • Thiazolidinediones
  • troglitazone sulfate
  • Hydrolases
  • fumarylacetoacetase
  • Troglitazone