Application of quantitative time-lapse imaging (QTLI) for evaluation of Mrp2-based drug-drug interaction induced by liver metabolites

Toxicol Appl Pharmacol. 2012 Sep 1;263(2):244-50. doi: 10.1016/j.taap.2012.06.016. Epub 2012 Jul 2.


We previously reported a quantitative time-lapse imaging (QTLI)-based analysis method to assess drug-drug interactions (DDI) at multidrug resistance-associated protein 2 (Mrp2) in rat sandwich-cultured hepatocyte (SCH) system, utilizing the fluorescent Mrp2 substrate, 5-(and 6)-carboxy-2',7'-dichlorofluorescein (CDF). Here, we aimed to examine the feasibility of using QTLI to evaluate DDI involving drug metabolite(s) generated in hepatocytes. We used estradiol (E2) and bilirubin as model compounds; both are not substrates of MRP2, whereas their hepatic metabolites, estradiol-17β-glucuronide (E17G) or bilirubin glucuronides, are known to be its substrates as well as inhibitors. When rat SCHs were pre-exposed with E2, fluorescence of CDF accumulated in bile canaliculi decreased depending upon both the duration of pre-exposure and the concentration of extracellular E2. The decrease corresponded with the increase in intracellular concentration of E17G in hepatocytes. Furthermore, cytotoxicity of vinblastine, a substrate of MRP2, was enhanced in SCHs treated with E2. Similarly, CDF accumulated in bile canaliculi was significantly reduced in rat SCHs pre-exposed with bilirubin. In conclusion, these results suggest that phase II biotransformation of a competitor is reflected in alteration of MRP2-mediated CDF transport detected in QTLI. The QTLI might provide a convenient platform to evaluate transporter-based DDIs involving hepatic metabolites of drug candidates without the need to identify the metabolites.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Binding Cassette Transporters / metabolism*
  • Animals
  • Antineoplastic Agents, Phytogenic / pharmacology
  • Bilirubin / administration & dosage
  • Bilirubin / analogs & derivatives
  • Bilirubin / metabolism
  • Bilirubin / pharmacology
  • Cell Culture Techniques
  • Drug Interactions
  • Estradiol / administration & dosage
  • Estradiol / analogs & derivatives
  • Estradiol / metabolism
  • Estradiol / pharmacology
  • Feasibility Studies
  • Fluoresceins / chemistry
  • Hepatocytes / metabolism*
  • Male
  • Rats
  • Rats, Wistar
  • Time-Lapse Imaging / methods*
  • Vinblastine / pharmacology*


  • ATP-Binding Cassette Transporters
  • Abcc2 protein, rat
  • Antineoplastic Agents, Phytogenic
  • Fluoresceins
  • 5(6)-carboxy-2',7'-dichlorofluorescein
  • estradiol-17 beta-glucuronide
  • bilirubin glucuronate
  • Estradiol
  • Vinblastine
  • Bilirubin