Increased expression of messenger ribonucleic acid encoding cytochrome P450 cholesterol side-chain cleavage and P450 17alpha-hydroxylase enzymes in ovarian hyperthecosis

Approach to Investigation of Hyperandrogenism in a Postmenopausal Woman

Postmenopausal hyperandrogenism is a condition caused by relative or absolute androgen excess originating from the ovaries and/or the adrenal glands. Hirsutism, i.e., increased terminal hair growth in androgen-dependent areas of the body, is considered the most effective measure of hyperandrogenism in women. Other symptoms can be acne and androgenic alopecia or the development of virilization including clitoromegaly. Postmenopausal hyperandrogenism may also be associated with metabolic disorders like abdominal obesity, insulin resistance and type 2 diabetes. Mild hyperandrogenic symptoms can be due to relative androgen excess associated with menopausal transition or polycystic ovary syndrome, which is likely the most common cause of postmenopausal hyperandrogenism. Virilizing symptoms, on the other hand, can be caused by ovarian hyperthecosis or an androgen-producing ovarian or adrenal tumor that may be potentially malignant. Determination of serum testosterone, preferably by tandem mass spectrometry, is the first step in the endocrine evaluation providing important information on the degree of androgen excess. Testosterone > 5 nmol/L is associated with virilization and requires prompt investigation to rule out an androgen-producing tumor in first instance. To localize the source of androgen excess, imaging techniques are used like transvaginal ultrasound or magnetic resonance imaging (MRI) for the ovaries and computed tomography (CT) and MRI for the adrenals. Bilateral oophorectomy or surgical removal of an adrenal tumor is the main curative treatment and will ultimately lead to a histopathological diagnosis. Mild to moderate symptoms of androgen excess are treated with anti-androgen therapy or specific endocrine therapy depending on diagnosis. This review summarizes the most relevant causes of hyperandrogenism in postmenopausal women and suggests principles for clinical investigation and treatment.

Hyperthecosis: an underestimated nontumorous cause of hyperandrogenism

Hyperthecosis is defined as the presence of nests of luteinized theca cells in the ovarian stroma. Persistent testosterone released by ovarian theca cells is unmasked postmenopausally through the loss of granulosa cell-mediated aromatization of testosterone to estradiol. Ovarian hyperthecosis (OH) usually presents with symptoms of hyperandrogenism and is often described as a severe or extreme form of Polycystic Ovary Syndrome (PCOS). Serum testosterone levels in excess of 150 ng/dl (>5.2 nmol/l) are seen in affected patients and this threshold is used to confirm a diagnosis. Treatment of hyperthecosis is multi-faceted. It addresses the attendant hyperandrogenism (hirsutism and virilization) as well as metabolic complications such as obesity and insulin resistance. Ultimately, laparoscopic bilateral salpingo-oophorectomy is definitive treatment. This remains the treatment of choice in postmenopausal women whereas treatment using GnRH agonists may be used in women of reproductive age, especially younger women. Nevertheless, if serum testosterone remains elevated despite several months of therapy with a GnRH agonist, surgery is often required for biopsy sample collection and further definitive therapy. In order to mitigate the common clinical manifestations of hyperandrogenism, anti-androgen therapy (either cyproterone acetate or spironolactone) may be used to suppress the actions of testosterone on tissues. In patients with impaired glucose metabolism and insulin resistance, Metformin should also be considered as part of treatment. Combined, such a treatment regimen will often lead to decreased ovarian androgen secretion.

Immunodetection and quantification of enzymatic markers in theca cells: the early process of ovarian steroidogenesis†

The association between theca cells (TCs) and granulosa cells is pivotal to steroid biosynthesis in the ovary. During the late secondary follicle stage, TCs form a layer around granulosa cells, after which their steroidogenic function falls under the control of luteinizing hormone (LH) that activates the cAMP signaling pathway via a G protein-coupled receptor. In addition to perilipin-2, a marker for lipid droplets containing esters as substrates for TCs to produce steroidogenic hormones, other essential proteins, like steroidogenic acute regulatory protein (StAR), cytochrome P450 11A1, cytochrome P450c17, 3 beta-hydroxysteroid dehydrogenase/delta 5 -> 4-isomerase type 1, and 3 beta-hydroxysteroid dehydrogenase/delta 5 -> 4-isomerase type 2, play a role in the cascade after luteinizing hormone-choriogonadotropic hormone receptor (LH/CG-R) occupation by LH. The aim of the present study was to assess expression levels and corresponding amounts of LH/CG-R, perilipin-2, and enzymes involved in the steroidogenic pathway of TCs based on follicle stage. Immunohistochemical analysis of each of these proteins was therefore performed on ovarian samples from nine adult women, most (n = 8) with BRCA1 and/or BRCA2 mutations undergoing prophylactic bilateral oophorectomy. Pictures were taken of the theca layer of secondary, small (<3000 μm), and large (>3000 μm) antral follicles and corpora lutea at 100× magnification. ImageJ software was used to analyze the surface area and expression intensity of each protein at each stage, known as the staining index. Overall, our data showed that LH/CG-R, perilipin-2, and StAR expression increased in the course of folliculogenesis and luteinization. Similarly, cytochrome P450 11A1, cytochrome P450c17, 3 beta-hydroxysteroid dehydrogenase/delta 5 -> 4-isomerase type 1, and 3 beta-hydroxysteroid dehydrogenase/delta 5 -> 4-isomerase type 2 expression were substantially elevated in TCs during folliculogenesis, evidenced by their coordinated action in terms of area covered and expression intensity. This study, conducted for the first time on human ovarian tissue, contributes to localizing and quantifying expression of key steroidogenic proteins at both intracellular and tissue levels. These findings may shed new light on pathological conditions involving the human ovary, such as androgen-secreting tumors of the ovary and other disorders associated with ovarian TCs in patients with polycystic ovary syndrome.

[Post-menopausal ovarian hyperthecosis]

Ovarian hyperthecosis is infrequent but it represents the first cause of post-menopausal hyperandrogenia. Pathophysiology of ovarian hyperthecosis remains poorly understood but the metabolic syndrome observed in most patients suggests that insulin resistance associated with high, postmenopausal LH levels, might play a role as in polycystic ovarian syndrome. We report here four patients who presented post-menopausal hyperandrogenia. Although high, tumoral, plasma testosterone levels, lack of focused radiological lesions except enlarged ovaries, associated to the metabolic syndrome, suggested ovarian hyperthecosis. Bilateral annexectomy allowed histological confirmation of hyperthecosis showing specific luteinized stromal cells and led to the complete suppression of the inappropriate androgen secretion.

Polycystic ovary syndrome. A diagnostic challenge

Polycystic ovary syndrome remains a diagnostic challenge because there is no single defining test. The clinical presentation must dictate the extent of the work-up. The typical PCOS patient has a history of irregular menses and appears hirsute. Demonstration of ovulatory dysfunction and hyperandrogenism can also be made by appropriate hormonal measurements. An ultrasound showing multiple small ovarian follicles can support a diagnosis of PCOS in the patient for whom the clinical diagnosis has been made. Other causes of hyperandrogenism and ovulatory dysfunction should be excluded.