Host: The Japanese Society of Toxicology
Name : The 50th Annual Meeting of the Japanese Society of Toxicology
Date : June 19, 2023 - June 21, 2023
Endocrine-disrupting chemicals can interfere with endocrine systems and induce various harmful effects including reproductive toxicity. As for evaluation of the estrogenic properties of chemicals, the uterotrophic bioassay has been proposed as an in vivo screening test in the OECD testing framework; however, estrogenic activities evaluated by this bioassay may be underestimated when test chemicals exhibit no effects on the uterus. To address these problems, we generated an estrogen-responsive reporter transgenic (E-Rep) mouse. We here investigated the estrogen-disrupting potential of following two heavy metals.
Cadmium (Cd) accumulates in rice and chronic exposure to Cd from rice is of a major concern. Some studied reported that Cd can exhibit endocrine disrupting actions through its estrogen-like action. In contrast, others have reported no relationship between Cd exposure and estrogen-related diseases. Thus, the detail estrogenic actions of Cd, including their authenticity, have not been fully understood.
Organotin compounds, such as tributyltin chloride (TBT), have been widely used as antifouling agents on the hulls of ships. Although the use of organotins in paints is currently internationally regulated, there is concern about harmful effects of chronic exposure to organotins from contaminated fish and solids. TBT has been reported to induce abnormal estrus cycle and decreased pregnancy rate in female rat. We here showed that organotins can disrupt estrogen signaling through nuclear receptors (peroxisome proliferator-activated receptor γ and retinoid X receptor), and subsequently induce abnormal estrus cycle in mice.
In this symposium, we will introduce our studies using E-Rep mouse and discuss the estrogen-disrupting potential of above two heavy metals.
