Endocrine Abstracts

In our daily life, humans are exposed to lots of chemicals. Among those chemicals, octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5) have been widely used in cosmetics for their functions such as softening, wetting, and viscosity control. However, the effect of these chemicals on the female reproductive systems has not been clearly elucidated. In the case of D4, it was recently recognized as an endocrine disrupting chemical (EDC), but the effect of D5 has been unknown. In vitro study, the human uterus epithelial-like Ishikawa cells, were treated with D4 and D5 to measure cell viability. In both D4 and D5 showed, decreased in cell viability at the 10^-4 M. It means both chemicals are toxic in uterus. In vivo study, female Sprague Dawley rats were exposed to D4 and D5 diluted in corn oil for 2 weeks. At this time corn oil (Vehicle), 60 mg/kg/day (D4), and 100 mg/kg/day (D5) were administrated by using oral injection. Result shows there was no significant difference in uterine epithelial and stromal marker gene expression. On the other hand, ovary folliculogenesis and steroidogenesis gene expression were varied. HE staining results showed that increased uterine glands and ovary follicles number. Therefore, this study suggests that D4 and D5 aggravated female reproductivity such as miscarriage and implantation failure.

Acknowledgement: This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT) (No. 2021R1A2C2093275).