Steroids

Steroid hormones participate in organ development, reproduction, body homeostasis, and stress responses. The steroid machinery is expressed in a development- and tissue-specific manner, with the expression of these factors being tightly reg…

Endometriosis, defined as the presence of endometrial glands and stroma at extra-uterine sites, is a gynecological condition that affects women of reproductive age. Consistent with its uterine origins, endometriotic lesions and resulting sy…

Estrogens are synthesized by the aromatase enzyme encoded by the Cyp19a1 gene, which contains an unusually large regulatory region. In most mammals, aromatase expression is under the control of two distinct promoters a gonad- and a brain-sp…

Dienogest was introduced as an oral progestin. Yet its strong oral potency on endometrial activity is not clearly explained. To circumvent this situation, steroid hormone receptor profiling using transactivation assay and endometrial activi…

Progesterone receptor modulators have diverse potential therapeutic uses, including the treatment of endometriosis, uterine fibroids and breast cancer. Here we describe the molecular properties and preclinical pharmacology of a new steroida…

Tibolone is a highly effective postmenopausal hormone treatment that has its biological activity dependent on metabolism to 3alpha- and 3beta-OH tibolone, which bind solely to the estrogen receptor. Despite the high levels of estrogen recep…

A variety of progestins are available for therapeutic use. It is convenient to classify them into those related in chemical structure to progesterone or testosterone. Progestins related to progesterone can be subdivided into pregnanes and 1…

Asoprisnil is a novel selective steroid receptor modulator that shows unique pharmacodynamic effects in animal models and humans. Asoprisnil, its major metabolite J912, and structurally related compounds represent a new class of progesteron…

CDB-2914 (17 alpha-acetoxy-11 beta-[4-N,N-dimethylaminophenyl]-19-norpregna-4,9-diene-3,20-dione) is a 19-norprogesterone derivative that acts as an antagonist in progesterone-responsive tissues. It binds to progesterone receptors A and B w…

Aromatase is the rate limiting enzyme that catalyzes the conversion of androgens to estrogens. Blockade of this step allows treatment of diseases that are dependent upon estrogen. Over the past two decades, highly potent and specific aromat…

Under the influence of ovarian steroid hormones, endometrial cells aer able to produce a wide variety of growth factors and peptide hormones that area believed to promote: (1) physiological growth and differentiation during the endometrial …

CDB(VA)-2914 (17alpha-acetoxy-11beta-(4-N,N-dimethylaminophenyl)-19-norpregna-4,9-diene-3,20-dione) is a synthetic steroid that demonstrates potent progesterone antagonist activity in vitro and in vivo. Its binding and antagonist potency wi…

Since the original description of the structure of the antiprogestin, mifepristone, was published, numerous related compounds have been synthesized which may function as progesterone antagonists (PAs) or progesterone receptor modulators (PR…

Expression of tissue factor (TF), the primary initiator of hemostasis via thrombin formation, is induced during progesterone (P4)-stimulated decidualization of human endometrial stromal cells (HESCs), and remains elevated in decidualized HE…

Unscheduled disturbances of bleeding with long-acting progestogen-only methods continue to be a major social inconvenience, and the most common reason for premature discontinuation of use. The patterns of bleeding with different methods are…

Both progesterone receptor modulators (PRMs) as well as pure progesterone antagonists (PAs) have numerous proven and potential therapeutic applications in female health care. Mifepristone, a PRM with only marginal agonistic activity, togeth…

Ovarian stimulation with gonadotropins (GN) during human in vitro fertilization and embryo transfer (IVF/ET) therapy alters the ovarian steroid output, especially that of progesterone. As a consequence, endometrial transformation is advance…

An increase in androgen receptor (AR) caused by estrogen is recognized as one of the biological phenomena related to estrogen-induced growth in uterine endometrium. The A/B region of AR gene in X chromosome involves the cytosine, adenine, a…

Endometriosis is a benign, though aggressive, disease of the female reproductive tract that consists of endometrial stromal and epithelial cells growing at an extrauterine site. Although it is widely accepted that the majority of cases of e…

The biotransformation of the progestagen dienogest (17 alpha-cyanomethyl-17 beta-hydroxy-4,9-estradien-3-one) was studied in vivo in female rabbits and in vitro by liver homogenates from female rabbits and rats. In vivo, in the female rabbi…

Mifepristone (RU 486), used clinically for the termination of early pregnancy, and its acetyl and 13-retro (13 alpha) analogs show potent antiproliferative effects against estrogen-dependent human breast tumors and endometriosis. However, t…

Antiprogestins of the 11 beta-aryl-substituted 19-norsteroid family are effectively used in inhibiting nidation and in terminating pregnancies. They are potentially useful in the treatment of progesterone-related diseases such as meningioma…

The interrelationship between estrogen and insulin-like growth factor-I (IGF-I) in the regulation of uterine growth was studied in the rat. The levels of the estrogen receptor (ER), ER mRNA, and IGF-I mRNA in rat uterus and liver were monit…

The suppressive effects of Danazol, an isoxazol derivative of the synthetic steroid 17 alpha-ethinyltestosterone, on endometrial DNA synthesis were investigated in rats by immunohistochemistry with bromodeoxyuridine (BrdU) and DNA-synthesiz…

The sequence of events within the ovary during the process of ovulation discussed in this review is schematically represented in Fig. 1. It is obvious that LH, perhaps with some contribution from FSH, is the normal physiological trigger for…