TY - JOUR
T1 - 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
AU - Matsuoka-Kawano, Kazuaki
AU - Yoshinari, Kouichi
AU - Nagayama, Sekio
AU - Yamazoe, Yasushi
PY - 2010/4
Y1 - 2010/4
N2 - (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 [3H]-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.
AB - (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 [3H]-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.
KW - Aryl hydrocarbon receptor
KW - CYP induction
KW - Ligand binding assay
KW - SiRNA
KW - TSU-16
UR - http://www.scopus.com/inward/record.url?scp=77950935687&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77950935687&partnerID=8YFLogxK
U2 - 10.1016/j.cbi.2010.02.014
DO - 10.1016/j.cbi.2010.02.014
M3 - Article
C2 - 20171196
AN - SCOPUS:77950935687
VL - 185
SP - 33
EP - 41
JO - Chemico-Biological Interactions
JF - Chemico-Biological Interactions
SN - 0009-2797
IS - 1
ER -