Zearalenone metabolism in human placental subcellular organelles, JEG-3 cells, and recombinant CYP19A1

•Zearalenone and zearalanone is metabolized to their hydroxyl metabolites in placenta.•CYP19A1 but not reductase enzyme is capable to metabolize zearalenone and zearalanone.•These compounds may interfere with physiological placental estrogen signaling.

Zearalenone (ZEN) and its derivative, zearalanone (ZAN), are endocrine disruptive mycotoxins produced by Fusarium species. We investigated the human placental metabolism of ZEN and ZAN in vitro in JEG-3 cells, human term placental subcellular fractions and recombinant enzymes. Human placental enzymes were capable of metabolizing ZEN and ZAN to their primary OH-metabolites which have higher affinity for estrogen receptors than their parent compounds. These metabolites may interfere with physiological placental estrogen signaling and thus disrupt the progress of gestation.