TSU-16, (Z)-3-[(2,4-dimethylpyrrol-5-yl)methylidenyl]-2-indolinone, is a potent activator of aryl hydrocarbon receptor and increases CYP1A1 and CYP1A2 expression in human hepatocytes.
(Z)-3-[(2,4-dimethylpyrrol-5-yl)methylidenyl]-2-indolinone (TSU-16), is a potent anti-angiogenic agent that inhibits the tyrosine kinase of vascular endothelial growth factor receptor-2. In clinical trials with daily or twice weekly intravenous administration of TSU-16, its increased clearance was observed. To understand the mechanism underlying this observation, we have investigated the TSU-16-mediated regulation of cytochrome P450 expression. In human hepatocytes, TSU-16 increased mRNA levels of CYP1A1 and CYP1A2, but not CYP2B6 and CYP3A4. The extent of increase and profiles of the time-dependent changes in CYP1A1 and CYP1A2 mRNA levels after TSU-16 treatment were similar to those after treatment with 3-methylcholanthrene (3MC), a well-known activator of the aryl hydrocarbon receptor (AhR). In reporter assays using a plasmid construct that contained the human CYP1A1 5'-flanking region including the region crucial for the AhR-dependent transcription of both human CYP1A1 and CYP1A2, TSU-16 treatment increased reporter activities to an extent similar to that obtained with 3MC. Treatment of HepG2 cells and human hepatocytes with AhR-targeting siRNA suppressed the increase in both mRNA levels and CYP1A activities after treatment with TSU-16 as well as after that with omeprazole or 3MC. TSU-16 also time-dependently reduced cellular AhR protein levels in HepG2 cells to a similar extent with 3MC treatment. Furthermore, we demonstrated that unlabeled TSU-16 and 3MC but not omeprazole completely inhibited the specific binding of [(3)H]-3MC to mouse Hepa1c1c7 cytosol, suggesting TSU-16 as an AhR ligand. In conclusion, our present results suggest that TSU-16 binds to and activates AhR to enhance the expression of both human CYP1A1 and CYP1A2. Because TSU-16 is metabolized mainly by CYP1A2, its increased clearance after repeated dosing may be attributed to the enhanced expression of hepatic CYP1A2.
Matsuoka-Kawano
Kazuaki
K
Division of Drug Metabolism and Molecular Toxicology, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba-ku, Sendai, Miyagi, Japan. kazu-matsuoka@taiho.co.jp
Yoshinari
Kouichi
K
Nagayama
Sekio
S
Yamazoe
Yasushi
Y
D000328:Adult; D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D002478:Cells, Cultured; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics* / Q000378:metabolism; D019388:Cytochrome P-450 CYP1A2 / Q000235:genetics* / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D056945:Hep G2 Cells; D022781:Hepatocytes / Q000378:metabolism*; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D011485:Protein Binding; D011758:Pyrroles / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics; D018336:Receptors, Aryl Hydrocarbon / Q000819:agonists / Q000378:metabolism*; D055815:Young Adult
C549241:3-((2,4-dimethylpyrrol-5-yl)methylidenyl)-2-indolinone; D020533:Angiogenesis Inhibitors; D007211:Indoles; D011758:Pyrroles; D012333:RNA, Messenger; D018336:Receptors, Aryl Hydrocarbon; D019363:Cytochrome P-450 CYP1A1; D019388:Cytochrome P-450 CYP1A2