Ah receptor agonist activity in frequently consumed food items

Abstract

The aryl hydrocarbon receptor (AhR) receives much attention for its role in the toxicity of dioxins and dioxin-like polychlorinated biphenyls. However, many other compounds have also been reported to bind and activate AhR, of which natural food components are of special interest from a human health perspective. Using the dioxin receptor–chemical-activated luciferase gene expression (DR CALUX®) bioassay, extracts from many food items frequently consumed in the Netherlands were screened to estimate the intake of natural AhR agonists (NAhRAs). Using the prototypical AhR agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as standard, it was estimated that the daily intake of NAhRAs might be considerably higher than the reported intake of dioxins and dioxin-like polychlorinated biphenyls. Potatoes, cruciferous vegetables, bread, hamburgers, and grapefruit juice contained most NAhRAs. Food preparation and acid treatment can show a significant effect on AhR activation. The interaction of natural and xenobiotic AhR agonists should be taken into account when performing risk–benefit analysis of both types of compounds.

Keywords:

• aryl hydrocarbon receptor (AhR)
• 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)
• food
• fytochemicals
• dioxin receptor–chemical-activated luciferase gene expression (DR CALUX®) assay

Acknowledgement

The authors thank Kyoko Sato, Liza Portier, Karin Van Ede, and Cornelis Van De Kraats for their important contribution to the sample treatment; and the DR CALUX® analysis. The Dutch Centre of Human Nutrigenomics (CHN) supported this study.