The aryl hydrocarbon receptor (AhR, also called dioxin receptor) is a ligand-activated transcription factor and is known to mediate biological and toxicological effects of polycyclic aromatic hydrocarbons such as 2,3,7,8-tetrachrolodibenzo-p-dioxin (TCDD). We found certain natural flavonoids belonging to the flavone, flavonol, flavanone, flavan-3-ol and chalcone subgroups acted as the antagonists of AhR. As the mechanism, effective flavonoids competed the binding of agonist to the AhR and suppressed the TCDD-induced nuclear translocation of the AhR and dissociation of its partner proteins, heat shock protein 90 and X-associated protein 2. Subsequently, these flavonoids inhibited phosphorylation of both AhR and AhR nuclear translocator (Arnt), and the formation of a heterodimer consisting of these proteins. It was confirmed that effective flavonoids suppressed the agonist-induced activation of AhR in animal experiment. In conclusion, certain natural flavonoids can modulate the function of AhR and suppress biological and toxicological effects of dioxins.

Natural flavonoids can modulate the function of dioxin receptor

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.