Effects of phytoestrogens genistein and daidzein on progesterone and estrogen (estradiol) production of human term trophoblast cells in vitro

Abstract

Objective. Phytoestrogens are a diverse group of nonsteroidal plant compounds that occur naturally in many plants. Because they possess a ring system similar to estrogens they are able to bind on estrogen receptors alpha and beta in humans. The effects of the phytoestrogens genistein and daidzein on the production of progesterone and estrogen in isolated human term trophoblast cells in vitro were tested in this study.

Material and methods. Cytotrophoblast cells were isolated from human term placentas. Phytoestrogens genistein and daidzein were incubated in different concentrations with trophoblast cells. Untreated cells were used as controls. After 24 h aliquots were removed and tested for progesterone and estrogen production.

Results. The production of the steroid hormones progesterone and estrogen are influenced by phytoestrogens genistein and daidzein in human term trophoblast cells. A strong inhibition effect of both phytoestrogens tested in the production of progesterone was demonstrated. In addition, a significant stimulating effect on estrogen production by genistein and daidzein was observed.

Conclusion. Results obtained with this study show that phytoestrogens (genistein and daidzein) sufficiently reduce progesterone production in human term trophoblast cells. Because blockade of progesterone is a possible mechanism involved in initiation of labor, we may speculate that high doses of phytoestrogens at the feto-maternal interphase could play a negative role in maintenance of pregnancy. Stimulation of estrogen production by genistein and daidzein in trophoblast cells is probably due to estrogen receptor blocking effects of both phytoestrogens. Trophoblast cells seem to compensate blocking of its estrogen receptors by higher estrogen production.

Keywords:

• Genistein
• daidzein
• progesterone
• estradiol
• human term trophoblast cells