Androgens, although traditionally thought to be male sex steroids, play important roles in female reproduction, both in healthy and pathological states. This mini-review focuses on recent advances in our knowledge of the role of androgens in the ovary. Androgen receptor (AR) is expressed in oocytes, granulosa cells, and theca cells, and is temporally regulated during follicular development. Mouse knockout studies have shown that AR expression in granulosa cells is critical for normal follicular development and subsequent ovulation. In addition, androgens are involved in regulating dynamic changes in ovarian steroidogenesis that are critical for normal cycling. Androgen effects on follicle development have been incorporated into clinical practice in women with diminished ovarian reserve, albeit with limited success in available literature. At the other extreme, androgen excess leads to disordered follicle development and anovulatory infertility known as polycystic ovary syndrome (PCOS), with studies suggesting that theca cell AR may mediate many of these negative effects. Finally, both prenatal and postnatal animal models of androgen excess have been developed and are being used to study the pathophysiology of PCOS both within the ovary and with regard to overall metabolic health. Taken together, current scientific consensus is that a careful balance of androgen activity in the ovary is necessary for reproductive health in women.
PMID 30912811 30912811 DOI 10.1210/en.2019-00101 10.1210/en.2019-00101 Astapova et al. 2019, Astapova 2019
Cite this article
Astapova, O., Minor, B. M. N., & Hammes SR (2019). Physiological and Pathological Androgen Actions in the Ovary. Endocrinology, 160(5), 1166-1174. https://doi.org/10.1210/en.2019-00101
Astapova O, Minor BMN, Hammes SR. Physiological and Pathological Androgen Actions in the Ovary. Endocrinology. 2019;160(5):1166-1174. doi:10.1210/en.2019-00101
Astapova, O., et al. "Physiological and Pathological Androgen Actions in the Ovary." Endocrinology, vol. 160, no. 5, 2019, pp. 1166-1174.
Polycystic ovarian syndrome (PCOS) is a metabolic, reproductive, and psychological complex series of disorders that impacts a woman throughout her lifespan. PCOS is a disorder of hormonal imbalance occurring in women of reproductive age. This disorder is characterized by high levels of male androgens like testosterone. This can lead to symptoms like irregular periods, amenorrhea (absence of menstruation), anovulation (absence of ovulation), hirsutism, acne, and obesity. PCOS also causes metabolic impairment. Multiple peripherally arranged immature follicles of about 2-5mm in diameter are present in the ovary. These follicles do not mature due to hormonal imbalances leading to an irregular menstrual cycle. PCOS is a metabolic, reproductive, and psychological complex series of disorders that impacts a woman throughout her lifespan. Polycystic ovarian syndrome is not a fatal or life-threatening disorder as its main complication is infertility. PCOS can be a root cause of serious medical conditions like obesity, hypertension, type-2 diabetes mellitus due to insulin resistance, endometrial cancers, ovarian cancer, etc. Stress may cause the hormone levels in the pituitary to fluctuate. Since the menstrual cycle is hormone-based, there are apparent irregularities.
Rosenfield RL et al., 2016·Endocrine reviews·
Open Access
Polycystic ovary syndrome (PCOS) was hypothesized to result from functional ovarian hyperandrogenism (FOH) due to dysregulation of androgen secretion in 1989-1995. Subsequent studies have supported and amplified this hypothesis. When defined as otherwise unexplained hyperandrogenic oligoanovulation, two-thirds of PCOS cases have functionally typical FOH, characterized by 17-hydroxyprogesterone hyperresponsiveness to gonadotropin stimulation. Two-thirds of the remaining PCOS have FOH detectable by testosterone elevation after suppression of adrenal androgen production. About 3% of PCOS have a related isolated functional adrenal hyperandrogenism. The remaining PCOS cases are mild and lack evidence of steroid secretory abnormalities; most of these are obese, which we postulate to account for their atypical PCOS. Approximately half of normal women with polycystic ovarian morphology (PCOM) have subclinical FOH-related steroidogenic defects. Theca cells from polycystic ovaries of classic PCOS patients in long-term culture have an intrinsic steroidogenic dysregulation that can account for the steroidogenic abnormalities typical of FOH. These cells overexpress most steroidogenic enzymes, particularly cytochrome P450c17. Overexpression of a protein identified by genome-wide association screening, differentially expressed in normal and neoplastic development 1A.V2, in normal theca cells has reproduced this PCOS phenotype in vitro. A metabolic syndrome of obesity-related and/or intrinsic insulin resistance occurs in about half of PCOS patients, and the compensatory hyperinsulinism has tissue-selective effects, which include aggravation of hyperandrogenism. PCOS seems to arise as a complex trait that results from the interaction of diverse genetic and environmental factors. Heritable factors include PCOM, hyperandrogenemia, insulin resistance, and insulin secretory defects. Environmental factors include prenatal androgen exposure and poor fetal growth, whereas acquired obesity is a major postnatal factor. The variety of pathways involved and lack of a common thread attests to the multifactorial nature and heterogeneity of the syndrome. Further research into the fundamental basis of the disorder will be necessary to optimally correct androgen levels, ovulation, and metabolic homeostasis.
Hilgers TW, 2004·The Medical and Surgical Practice of NaProTECHNOLOGY·
PCOS (polycystic ovary syndrome), increasingly designated PMOS (polycystic metabolic ovary syndrome) to reflect its metabolic complexity, is far more prevalent than its classic presentation suggests, affecting roughly six percent of reproductive-age women and carrying systemic consequences well beyond fertility disruption. This chapter from the foundational NaProTECHNOLOGY textbook maps the hormonal architecture of the condition, its ovulatory defect patterns, its frequent co-occurrence with endometriosis, and the restorative surgical and cycle-tracking approaches developed at the Pope Paul VI Institute.
Two long and broad streams of medical literature, from the 1950's to date, have established the existence of two unrelated abnormalities of androgen production in women with breast cancer. One is the genetically determined presence of subnormal production of adrenal androgens (i.e. DHEA and DHEAS) in women with premenopausal breast cancer and their sisters, who are at increased risk for breast cancer. The other is excessive production of testosterone, of ovarian origin, in subsets of women with either premenopausal or postmenopausal breast cancer and women with atypical breast-duct hyperplasia, who are at increased risk for breast cancer; along with the hypertestosteronism, there is frequently chronic anovulation in the premenopausal patients. The combination of ovarian hypertestosteronism and chronic anovulation is characteristic of the polycystic ovary syndrome and is also frequently seen in women with abdominal ("android") obesity; both PCOS and abdominal obesity are known to be characterized by high risk for postmenopausal cancer. The elevated testosterone levels and the increased levels of insulin, IGF-I, and IGF-II that are seen in PCOS and abdominal obesity could favor the development of breast cancer in several ways, all of which have been demonstrated experimentally: binding of testosterone to cancer cells bearing testosterone receptors, with direct stimulation; intratissular aromatization of testosterone to estradiol, with stimulation of estrogen-sensitive cells; stimulation of the production of epithelial growth factor (EGF) by testosterone, with direct mitogenic effect of EGF on cancer cells; stimulation of aromatase by insulin and IGF-I; direct mitogenic stimulation of cancer cells by insulin, IGF-I, and IGF-II; and stimulation by IGF-I and IGF-II of the intratissular reduction of estrone to estradiol. Since PCOS is probably largely genetically determined, and abdominal obesity may also be, the hypertestosteronism of these conditions may represent a second genetically determined hormonal risk factor for breast cancer.