Long-term in vitro exposure of human granulosa cells to the mixture of endocrine disrupting chemicals found in human follicular fluid disrupts steroidogenesis

Abstract

Most in vitro studies examine the effects of a single ED or a mixture of EDs on granulosa cells using short-term exposure; however, this approach is unlikely to reflect long-term, real-life exposures that are common in humans. We established an in vitro model that mimics long-term exposure of granulosa cells to real-life ED mixture. Human granulosa cells, HGrC1, were exposed to the mixture consisting of bisphenol A, polychlorinated biphenyl 153, benzo[a]pyrene, and perfluorooctanesulfonate in concentrations found in human follicular fluid (MIX) for 48 h and 4 weeks. Only long-term exposure to MIX decreased estradiol production after 2 and 3 weeks, and CYP19A1 protein after 2 weeks of exposure. By week 4, the cells restored estradiol production and CYP19A1 protein level. MIX increased basal progesterone production after 3 and 4 weeks of exposure but did not affect STAR and CYP11A1 mRNA. Cells that had been exposed to MIX for 4 weeks showed augmentation of forskolin-stimulated progesterone production. These results demonstrate that only long-term exposure to MIX alters steroidogenesis in HGrC1. This study also revealed that adverse effects of MIX on steroidogenesis in HGrC1 occurred a few weeks into MIX exposure and that this effect can be transient.

Keywords: ED mixture; Estradiol; Granulosa cells; HGrC1; Long-term exposure; Progesterone.