Effect of zeranol on expression of apoptotic and cell cycle proteins in murine placentae

- Zeranol administered at 1-100 mg/kg/day demonstrated an increasing trend of fetal resorption and early delivery in mice.
- Placental expression of Cdk2 and 4, Cyclin D1 and Bcl-xL were reduced mostly in mice treated with ≥10 mg zeranol/kg/day.
- Increased pErk-1 and 2 were also observed in the placentae of zeranol-treated mice.

Mycotoxins are chemicals produced by fungus and many of them are toxic to humans. Zeranol is a mycotoxin used to promote growth in cattle in North America; yet such a practice draws concern about the residual compound in meat in European countries. In the present study, the toxicity of zeranol was tested in a mouse model for reproduction. Pregnant ICR mice were given p.o. daily doses of zeranol at 0, 1, 10, 100 mg/kg for 4 days (from E13.5 to E16.5). Increased rates of fetal resorption at late gestation (E17.5) and preterm birth (