Accumulated inflammation and fibrosis participate in atrazine induced ovary toxicity in mice.

ABSTRACT

Atrazine is a widely used herbicide in agricultural production. Previous studies have shown that atrazine affects hormone secretion and oocyte maturation in female reproduction. However, the specific mechanism by which atrazine affects ovarian function remains unclear. In this study, using a mouse gastric lavage model, we report that four weeks of atrazine exposure affects body growth, interferes with the estrous cycle, and increases the number of atretic follicles in mice. The expression levels of follicle development related factors StAR, BMP15, and AMH decreased. Metabolomic analysis revealed that atrazine activates an inflammatory response in ovarian tissue. Further studies confirmed that the expression levels of TNF-α, IL-6, and NF-κB increased in the ovaries of mice exposed to atrazine. Additionally, α-smooth muscle actin (α-SMA) accumulated in ovarian tissue, and transforming growth factor-ß (TGF-ß) signaling was activated, indicating the occurrence of tissue fibrosis. Moreover, mice exposed to atrazine produced fewer oocytes and exhibited reduced embryonic development. Furthermore, mice exposed to atrazine exhibited altered gut microbiota abundance and a disrupted colon barrier. Collectively, these findings suggest that atrazine exposure induces ovarian inflammation and fibrosis, disrupts ovarian homeostasis, and impairs follicle maturation, ultimately reducing oocyte quality.