Phytoestrogen exposure alters endometrial stromal cells and interferes with decidualization signaling

Abstract

To investigate whether phytoestrogens (genistein and daidzein) alter invitro decidualization of human endometrial stromal cells (ESCs). Isolated primary ESCs were exposed to phytoestrogens and decidualized invitro. Academic fertility center. Twenty fertile oocyte donors attending the IVI Valencia clinic. Treatment of ESC with phytoestrogens at 0, 10, 20, 50, and 100μM. The ESC proliferation was analyzed by MTS assay. Invitro decidualization was induced in the presence of phytoestrogens by medroxyprogesterone acetate/cyclic adenosine 3':5' monophosphate and evaluated by prolactin (PRL) ELISA and F-actin immunostaining. The Ki67 proliferative marker was analyzed by immunofluorescence. The ESC apoptosis was assessed by annexin V/propidium iodide detection using flow cytometry. Estrogen (ERβ) and P receptor (PR) localization were evaluated by immunofluorescence. The ESC exposed to 0, 19, 20, 50, and 100μM of genistein, daidzein, and genistein + daidzein showed a dose-dependent proliferation decrease. After 48-96hours of culture, this reduction was significant in the presence of 50μM of phytoestrogens versus 10μM untreated ESC. The ESC decidualized in the presence of phytoestrogens did not rearrange their cytoskeletons and showed a significant decrease in PRL secretion compared with untreated decidualized ESCs (dESCs). However, phytoestrogens did not alter proliferative status or the percentage of viable/apoptotic cells in dESC compared with untreated dESC. During decidualization, phytoestrogens induced the same nuclear translocation of ERβ and PR as the control dESC. This study reveals that high doses of phytoestrogens could affect the invitro decidualization process.