Co-exposure to low levels of DEHP, procymidone, Cd2 + , Pb2+, and 1-nitropyrene may damage mouse ovary and uterus via Hippo pathway and circPVT1.

High doses of Di-(2-ethylhexyl) phthalate (DEHP), procymidone (PCM), Cd2+, Pb2+, and 1-nitropyrene (1-NP) induce reproductive toxicity in female experimental animals. However, evidence regarding female reproductive toxicity at low levels of combined exposure (co-exposure) to these substances is lacking. In this study, these environmental chemicals, which met or minimally exceeded the relevant standards, were administered simultaneously to 4-week-old female mice. After 21 days of exposure, the mice were kept feeding for 1 week and then sacrificed. Subsequently, their blood, ovaries, and uteri were taken. Co-exposure to concentrations ≥ 1/3 of the maximum allowable concentration (MAC) for each of these chemicals, as per relevant standards, was revealed to impair ovarian and uterine development in mice. This exposure activated the Hippo pathway, resulting in a decrease in ERα and circPVT1, and an elevation of miR-149. Co-exposure to these compounds in levels marginally lower than the MACs of each chemical also elevated cleaved CASPASE-3 levels. These changes showed a dose-response relationship. Joint exposure to these substances at values ≥ 1/3 of each average concentration in the blood could elicit similar biological effects in the ovaries and uteri cultured in vitro. Therefore, this study hypothesized that co-exposure to low levels of these environmental chemicals results in ovarian and uterine impairment in mice and that this damage may be linked to the activation of the Hippo pathway, downregulation of ERα and circPVT1, and upregulation of miR-149.