Background: Pregnant women have high serum concentrations of sex steroid hormones, which are major regulators of paracrine and autocrine responses for many maternal and placental functions. The main purpose of this study was to compare patients with preeclampsia and patients with uncomplicated pregnancies in terms of serum steroid hormones (estradiol [E2], progesterone [P4], dehydroepiandrosterone sulfate [DHEAS], and testosterone [T]) throughout pregnancy and the levels of cord blood and placental steroid receptors during the third trimester.
Methods: Quantitative real-time reverse transcription PCR, western blotting, and immunohistochemistry were used to determine the levels of steroid hormones in the serum and cord blood and the placental levels of estrogen receptor-α (ERα), ERβ, androgen receptor (AR), and progesterone receptor (PR).
Results: There were 45 women in the uncomplicated pregnancy group and 30 women in the preeclampsia group. Serum levels of T were greater and serum levels of E2 were reduced in the preeclampsia group, but the two groups had similar levels of P4 and DHEAS during the third trimester. Cord blood had a decreased level of DHEAS in the preeclampsia group, but the two groups had similar levels of P4, E2, and T. The two groups had similar placental mRNA levels of ERα, ERβ, AR, and PR, but the preeclampsia group had a higher level of ERβ protein and a lower level of ERα protein. Immunohistochemistry indicated that the preeclampsia group had a greater level of ERβ in the nucleus and cytoplasm of syncytiotrophoblasts and stromal cells.
Conclusions: Women with preeclampsia had lower levels of steroid hormones, estrogen, and ERα but higher levels of T and ERβ. These molecules may have roles in the pathogenesis of preeclampsia.
Keywords: Placenta; Preeclampsia; Sex steroids; Steroid receptor.