The UV filter benzophenone 3, alters early follicular assembly in rat whole ovary cultures

Abstract

Our goalwas to study the effect of BP3 (benzophenone 3) in the follicular assembly and thepotential involvement of Foxl2 pathway using whole ovary cultures. Ovaries werecollected from Wistar rats at birth, treated in vitro with vehicle (0.01 %DMSO), BP3 (5.8 nM, 276 nM, 576 nM and 876 nM) or ESR2 inhibitor (0.1 nM), andcultured for 7 days. Nest breakdown, follicular assembly and the expression ofseveral regulators of these processes (p27, Foxl2, Sox9, Bmp2, Cyp19 and Fst)were evaluated. In vitro exposure to BP3 (5.8 nM) decreased the population oftotal oocytes, the number of nests per ovary and early primary folliclespopulation. In addition, BP3 (5.8 nM) induced overexpression of Foxl2 mRNAlevels through ESR2 but increased Fst mRNA levels independently from ESR2 orFoxl2. We also observed that the number of p27-positive oocytes was decreasedafter BP3 (5.8 nM). On the other hand, exposure to BP3-276 increased totaloocytes, the number of nests per ovary and decreased primary follicles. Inaddition, BP3-276 induced no changes of Foxl2 mRNA levels through ESR2 but increasedFst mRNA levels independently from ESR2 or Foxl2. In conclusion, our studyclearly shows that exposure to BP3 is to perturb the early events of germ cell developmentas showed here in whole ovary cultures.