The Effects of Exogenous Estrogens on Estrogen Receptors in Male Reproductive Organs

Abstract

There is an essential physiological role for estrogen in male reproduction. Conversely, exposure to exogenous sources of estrogen has negative effects on reproductive physiology and fertility in men. Infertility, affecting nearly 15% of couples, is defined as the inability to conceive after one year of unprotected sexual intercourse. In at least 20% of cases, male reproductive pathology is the major cause for a couple’s infertility. Thus, it is essential to investigate potential causes of infertility in adult males. Evidence shows that exposure to certain endocrine disruptors is associated with reduced semen quality and impaired fertility in men. Bisphenol A and Diethylstilbestrol are endocrine disruptors that act as exogenous sources of estrogen and have been associated with male reproductive pathology. This review will examine the role of exogenous estrogens on changes in gene expression of estrogen receptors ERα, ERβ, and GPR30. Previous studies have had conflictive results, suggesting that the effects of exogenous estrogens on male reproduction are multi-faceted. Future studies should focus on determining whether exogenous estrogens have a stimulatory and/or inhibitory effect on gene expression and whether this relationship is dose-dependent or if it follows a more complex dosage pattern.