Although synthesis of estrogen by male gonads has been well documented for over half a century, it is only recently that the role of estrogen in male reproductive events has gained appreciation. We recently reported abundant expression of estrogen receptor (ER)-alpha and -beta in different cell types of the rat penis, whose levels diminished with advancing age. The present study, which builds o...

BACKGROUND Androgens and estrogens are crucial for mammalian sperm differentiation but their role in biology of mature male gamete is not still defined. The expression of proteins involved in the biosynthesis and action of these steroid hormones has been demonstrated in human spermatozoa, but very few data have been reported in mature sperm from non human species. The purpose of the current stu...

Aminoglutethimide, the first aromatase inhibitor, was established in the 1970s as an active treatment for patients with advanced breast cancer, but its lack of specificity was associated with side effects. Since that time, a series of much more specific non-steroidal aromatase inhibitors has been developed which are up to 10 000 times as potent as aminoglutethimide in vivo with no evidence of i...

Gonadal sex in the red-eared slider turtle is determined by the incubation temperature that the embryo experiences during the mid-trimester of development. High temperatures result in female-biased sex ratios, and low temperatures produce male-biased sex ratios. The physiological equivalent of temperature appears to be a combination of the nature and abundance of steroidogenic enzymes and their...

Introduction Genetic polymorphisms in CYP19 have been hypothesized to alter aromatase activity and have been examined in relationship with breast cancer risk (1–4). A greater frequency of tetranucleotide (TTTA)n repeat alleles in intron 4 have been reported among affected women (1,2). In a Scandinavian case-control study (cases/controls, 481/236) Kristensen et al. (4) observed a positive associ...

Many chemicals that adversely affect reproduction and/or development do so through multiple pathways within the reproductive tract and hypothalamic-pituitary-gonadal axis. Notable in this regard are fungicides, such as prochloraz or fenarimol, which in mammals have the potential to impact endocrine function through inhibition of CYP enzymes involved in steroid metabolism, as well as through ant...

Manipulation of the hormone oestrogen has been used for decades to treat hormone-dependent breast cancer. Currently, aromatase inhibitors (AIs) are used as first-line therapy against early and metastatic breast cancer in post-menopausal women. Despite these advances, several patients eventually experience a relapse of breast cancer and declined clinical response to treatment. As per recent find...

The control of placental hormone biosynthesis is critical during gestation, since their coordinated action is essential for the normal progress of pregnancy. Hormonal synthesis regulation in placenta is still not elucidated and differs from that observed in other steroidogenic tissues since specific tropic hormones have not yet been identified. Cellular localization of growth factors in the pla...

Sexual behaviors in green anoles are regulated by steroid hormones. Androgens activate the display of masculine courtship and copulatory behaviors, and estradiol activates feminine receptivity. Testosterone can also facilitate receptivity in females. The present study was conducted to test the role of converting testosterone to estradiol (aromatization) in the regulation of sexual and aggressiv...