Folic acid Ameliorates the Declining Quality of Sodium Fluoride-Exposed Mouse Oocytes through the Sirt1/Sod2 Pathway

Excessive sodium fluoride (NaF) intake interferes with reproductive function in humans and animals; however, strategies to prevent these effects are still underexplored. Here, we showed that in vivo and in vitro supplementation of folic acid (FA) efficaciously improved the quality of NaF-exposed oocytes. FA supplementation not only increased ovulation of oocytes from NaF-treated mice but also enhanced oocyte meiotic competency and fertilization ability by restoring the spindle/chromosome structure. Moreover, FA supplementation could exert a beneficial effect on NaF- exposed oocytes by restoring mitochondrial function, eliminating reactive oxygen species accumulation to suppress apoptosis. We also found that FA supplementation restored the defective phenotypes in oocytes through a Sirt1/Sod2-dependent mechanism. Inhibition of Sirt1 with EX527 abolished the FA-mediated improvement in NaF-exposed oocyte quality. Collectively, our data indicated that FA supplementation is a feasible approach to protect oocytes from NaF-related deterioration.