The in Vitro estrogenic activities of triclosan and triclocarban

Abstract

Triclosan (TCS) and triclocarban (TCC), as broad spectrum antibacterial agents, are distributed widely in the environment and humans. Most studies have focused on their distribution and biodegradation, but the endocrine-disrupting effects of these chemicals, especially their estrogenic effects, are still unclear. In the present study, we investigated the estrogenic effects of TCS and TCC using a series of in vitro assays, including the ER reporter gene assay in the CV-1 cells, E-screen assay and evaluation of estrogen-responsive genes in the MCF-7 cells. The tested concentrations of TCS and TCC were both from 1 × 10(-9) to 1 × 10(-6) M. Results showed that TCS and TCC exerted estrogenic activities by inducing luciferase activities in an ER reporter gene assay, promoting the proliferation of the MCF-7 cells, up-regulating the expression of pS2 and down-regulating ERα expression at both the mRNA and protein levels in the MCF-7 cells. We further found that TCS and TCC could alter the expression of multiple microRNAs (mir-22, mir-206 and mir-193b) in the MCF-7 cells, which would help understand the mechanisms of their estrogenic effects on regulating the expression of ERα. In brief, our results demonstrated the potential estrogenic effects and profiled in vitro data for further risk assessment of TCS and TCC.

Docking-Based Classification Models for Exploratory Toxicology Studies on High-Quality Estrogenic Experimental Data

“…On the other hand, triclosan is flagged as suspicious by our models and should, thus, be prioritized for further experimental testing. In this respect, recent mounting scientific evidence documents its adverse health effects: endocrine disruption, skin irritation and bacterial and antibiotic resistance [54].…”

Up-stream mechanisms for up-regulation of miR-125b from triclosan exposure to zebrafish (Danio rerio)

“…TCS is a type of weak estrogen that affects classical estrogen nuclear receptors (ERα and ERβ) (Gee et al, 2010;Huang et al, 2014). However, the present study demonstrated that TCS's estrogen activity results from its effects on GPER, a novel membrane receptor, rather than its effects on the classical ERα and ERβ receptors.…”

“…TCS has adverse effects on biological growth and development such as influencing reproduction and endocrine disorders. Many previous studies document the acute or long-term exposure toxicity of TCS to various organisms, such as fish, invertebrates and amphibians (Huang et al, 2014). For example, Yueh and Tukey (2016) found that long-term TCS exposure led to liver tumors and produced oxidative stress in mice.…”

Female Infertility and “Emerging” Organic Pollutants of Concern

“…It is structurally homologous to BPA [47], and experimental evidence in vitro indicates estrogenic, anti-estrogenic, and anti-androgenic activities [48,49], however not necessarily confirmed in vivo [46]. Still, experimental data reported a higher rate of implantation failures among mice treated with high doses of triclosan [50].…”