Pelargonidin activates the AhR and induces CYP1A1 in primary human hepatocytes and human cancer cell lines HepG2 and LS174T.

Abstract

We examined the effects of anthocyanidins (cyanidin, delphinidin, malvidin, peonidin, petunidin, pelargonidin) on the aryl hydrocarbon receptor (AhR)-CYP1A1 signaling pathway in human hepatocytes, hepatic HepG2 and intestinal LS174T cancer cells. AhR-dependent reporter gene expression in transfected HepG2 cells was increased by pelargonidin in a concentration-dependent manner at 24h. Similarly, pelargonidin induced the expression of CYP1A1 mRNA up to 5-fold in HepG2 and LS174T cells relative to the induction by 5 nM 2,3,7,8-tetrachlorodibenzodioxin (TCDD), the most potent activator of AhR. CYP1A1 and CYP1A2 mRNAs were also increased by pelargonidin in three primary human hepatocytes cultures (approximately 5% of TCDD potency) and the increase in CYP1A1 protein in HepG2 and LS174T cells was comparable to the increase in catalytic activity of CYP1A1 enzyme. Ligand binding analysis demonstrated that pelargonidin was a weak ligand of AhR. Enzyme kinetic analyses using human liver microsomes revealed inhibition of CYP1A1 activity by delphinidin (IC50 78 μM) and pelargonidin (IC50 33 μM). Overall, although most anthocyanidins had no effects on AhR-CYP1A1 signaling, pelargonidin can bind to and activate the AhR and AhR-dependent gene expression, and pelargonidin and delphinidin inhibit the CYP1A1 catalytic activity.

• Authors: Alzbeta Kamenickova, Eva Anzenbacherova, Petr Pavek, Anatoly A Soshilov, Michael S Denison, Pavel Anzenbacher, Zdenek Dvorak
• Journal: Toxicology letters (Toxicol Lett) Vol. 218 Issue 3 Pg. 253-9 (Apr 26 2013) ISSN: 1879-3169 [Electronic] Netherlands
• PMID: 23419638 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Chemical References

• AHR protein, human
• Anthocyanins
• Basic Helix-Loop-Helix Transcription Factors
• Ligands
• Polychlorinated Dibenzodioxins
• RNA, Messenger
• Receptors, Aryl Hydrocarbon
• pelargonidin
• CYP1A1 protein, human
• Cytochrome P-450 CYP1A1

Topics

• Anthocyanins (pharmacology)
• Basic Helix-Loop-Helix Transcription Factors (drug effects, metabolism)
• Cytochrome P-450 CYP1A1 (biosynthesis)
• Dose-Response Relationship, Drug
• Enzyme Induction
• Hep G2 Cells
• Hepatocytes (drug effects, enzymology)
• Humans
• Intestinal Neoplasms (enzymology)
• Kinetics
• Ligands
• Liver Neoplasms (enzymology)
• Microsomes, Liver (enzymology)
• Polychlorinated Dibenzodioxins (pharmacology)
• Primary Cell Culture
• Promoter Regions, Genetic (drug effects)
• RNA, Messenger (biosynthesis)
• Receptors, Aryl Hydrocarbon (drug effects, metabolism)
• Signal Transduction (drug effects)
• Transcriptional Activation (drug effects)
• Transfection