Clinical implications of hyperinsulinaemia in women

The role of AMH in the pathophysiology of polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS) affects 5 - 10% of reproductive age women, but its pathogenesis is still poorly understood. The aim of this review is to collate evidence and summarize our current knowledge of the role of anti-Müllerian hormone (AMH) in PCOS pathogenesis. AMH is increased and correlated with the various reproductive and metabolic/endocrine alterations in PCOS. AMH plays an inhibitory role in follicular development and recruitment, contributing to follicular arrest. AMH inhibitory action on FSH-induced aromatase production likely contributes to hyperandrogenism in PCOS, which further enhances insulin resistance in these women. Elevated serum AMH concentrations are predictive of poor response to various treatments of PCOS including weight loss, ovulation induction and laparoscopic ovarian drilling, while improvement in various clinical parameters following treatment is associated with serum AMH decline, further supporting an important role for AMH in the pathophysiology of this syndrome. This review emphasizes the need for understanding the exact mechanism of action of AMH in the pathophysiology of PCOS. This may lead to the development of new treatment modalities targeting AMH to treat PCOS, as well as help clinicians in prognostication and better tailoring existing treatments for this disease.

Possible Role of GnIH as a Mediator between Adiposity and Impaired Testicular Function

The aim of the present study was to evaluate the roles of gonadotropin-inhibitory hormone (GnIH) as an endocrine link between increasing adiposity and impaired testicular function in mice. To achieve this, the effect of GnIH on changes in nutrients uptake and hormonal synthesis/action in the adipose tissue and testis was investigated simultaneously by in vivo study and separately by in vitro study. Mice were treated in vivo with different doses of GnIH for 8 days. In the in vitro study, adipose tissue and testes of mice were cultured with different doses of GnIH with or without insulin or LH for 24 h at 37°C. The GnIH treatment in vivo showed increased food intake, upregulation of glucose transporter 4 (GLUT4), and increased uptake of triglycerides (TGs) in the adipose tissue. These changes may be responsible for increased accumulation of fat in white adipose tissue, resulting in increase in the body mass. Contrary to the adipose tissue, treatment with GnIH both in vivo and in vitro showed decreased uptake of glucose by downregulation of glucose transporter 8 (GLUT8) expressions in the testis, which in turn resulted in the decreased synthesis of testosterone. The GnIH treatment in vivo also showed the decreased expression of insulin receptor protein in the testis, which may also be responsible for the decreased testicular activity in the mice. These findings thus suggest that GnIH increases the uptake of glucose and TGs in the adipose tissue, resulting in increased accumulation of fat, whereas simultaneously in the testis, GnIH suppressed the GLUT8-mediated glucose uptake, which in turn may be responsible for decreased testosterone synthesis. This study thus demonstrates GnIH as mediator of increasing adiposity and impaired testicular function in mice.

Effects of seasonal adiposity on ovarian activity of Vespertilionid bat, Scotophilus heathi: proteomics analysis

In present study comparative proteomics was utilized to identify ovarian protein profiles and correlate the expression of these proteins with adiposity induced changes in ovarian activity leading to suppression of ovulation (delayed ovulation) in the bat, S. heathi. To achieve this, two-dimension gel electrophoresis combined with protein identification by tandem mass spectrometry (LC-MS/MS) was applied. Protein profiles were obtained from intact ovaries of bats collected during recrudescence (basal body weight) and delayed ovulation (increased body weight) phases of reproductive cycle. Out of 42 differentially expressed protein spots, 15 protein spots were identified by LC-MS/MS. A majority of the 15 protein spots identified belonged to a group of enzymes within the glycolytic and citrate cycles. Greater concentrations of these enzymes were found during the period of delayed ovulation, which may be responsible for an increase in the production of ATP within the ovary. The increased metabolic activity and energy production observed within the ovary during winter dormancy may be required for increased steroidogenic activity during this period. The protein 14-3-3 identified by LC-MS/MS was verified by immunoblotting, which confirmed its increased expression during the period of delayed ovulation and may be associated with development of insulin resistance. Treatment with adipokines (adiponectin, resistin) is responsible for increased expression of 14-3-3 protein in the ovary of S. heathi. Adiposity-associated rise in adipokines are thus responsible for increased expression of 14-3-3 protein in the ovary of S. heathi, which may be responsible for prolonged survival of antral follicles and suppression of ovulation. The 14-3-3 protein may represent a new marker for adiposity associated ovarian anovulation (disorders).

A study of pathogenesis of acanthosis nigricans and its clinical implications

Background:

Acanthosis nigricans (AN) is a dermatosis characterized by thickened, hyperpigmented plaques, typically on the intertriginous surfaces and neck. Common in some populations, its prevalence depends on race. Clinicians should recognize AN; it heralds disorders ranging from endocrinologic disturbances to malignancy. In this review, we discuss the pathogenesis of AN and its clinical implications and management.

Materials and Methods:

We selected 30 patients for the study. Diagnosis of associated disorders was established by history, physical examination, body mass index (BMI), hormone measurements by radioimmunoassays of thyroidnfunction tests, free testosterone, 17 (OH) progesterone, dehydroepiandrosterone sulfate (DHEAS), cortisol, gonadotropins, prolactin, immunoreactive insulin, and C-peptide levels.

Results and Discussion:

In our study, the flexural involvement (flexures of groins, knees and elbows) was seen in 40% patients, lip involvement was seen in 6.6% patients, and dorsal involvement was seen in 3.3% patients each. Increased serum testosterone levels were seen in 13.3% patients and increased DHEAS levels were seen in 20% patients. Regarding the types of AN, obesity induced AN or pseudo-AN was seen 70% patients, syndromic AN was seen in 23.35% patients and malignant AN was seen in 6.6% patients. The commonest histopathological feature of patients with AN was hyperkeratosis, seen in 100% patients, papillomatosis was seen in 90% patients, dermal infiltrate of lymphocytes and plasma cells was seen in 60% patients, horn pseudocysts were seen in 30% patients, and irregular acanthosis was seen in 26.6% patients.

Increased circulating leptin level inhibits folliculogenesis in vespertilionid bat, Scotophilus heathii

The present study investigates the mechanism by which obesity associated rise in leptin and insulin levels cause anovulation in vespertilionid bat, Scotophilus heathii. In the ovary of S. heathii, leptin and insulin receptors were mainly localized in interstitial and thecal cells and in the granulosa cells of primary follicles suggesting its possible role in androgen synthesis and follicular development. Adiposity associated increase in circulating leptin level down regulate ovarian LH-receptor expression and produce characteristic morphological changes in the antral follicles, such as hypertrophy of granulosa cells and a sharp decline in the rate of proliferation as well as apoptosis in the antral follicles. These follicles are referred as unique antral follicle. The in vitro study confirmed the in vivo findings that the high dose of leptin suppresses apoptosis and LH receptors. The present study thus showed that the adiposity associated increase in leptin during the first phase of follicular development inhibits folliculogenesis and simultaneously suppresses both follicular proliferation and apoptosis by reducing sensitivity to gonadotropin stimulation and decreasing circulating LH levels.

Anti-Müllerian hormone and polycystic ovary syndrome: a mountain too high?

Anti-Müllerian hormone (AMH) was initially thought to be produced solely by the foetal male during sexual differentiation to promote regression of the Müllerian ducts. Over the last decade, however, a new and interesting role has emerged for AMH in the ovary. In human ovaries, AMH is produced by granulosa cells from 36 weeks of gestation until menopause, with the highest expression being in small antral follicles. AMH production gradually declines as follicles grow; once follicles reach a size at which they are dominant, it has largely disappeared. Its removal from these larger follicles appears to be an important requirement for dominant follicle selection and progression to ovulation as AMH has an inhibitory role in the ovary, reducing both primordial follicle initiation and follicle sensitivity to FSH by inhibition of aromatase. It is for this reason that AMH is a focus of interest in polycystic ovary syndrome (PCOS). Serum levels are doubled, and granulosa cell production is greatly increased. Interestingly, there appear to be two groups of women with PCOS who can be distinguished by their AMH level: one group consists of those who have high levels which do not reduce with treatment and who respond less well to induction of ovulation, and a second group consists of those in whom the level is less elevated and reduces on treatment and who seem to respond rather better. Understanding the reason for the raised AMH in PCOS may give clues as to the mechanism of anovulation. To conclude, AMH appears to have a major inhibitory role during folliculogenesis, which may contribute to anovulation in PCOS.

Polycystic ovary syndrome in adolescents

BACKGROUND

Polycystic ovary syndrome (PCOS) is the commonest endocrine disorder in women and typically presents during adolescence. The clinical and biochemical presentation is heterogeneous, but elevated serum concentrations of androgens are the most consistent biochemical abnormality and may be considered to be the hallmark of the syndrome. Many women with PCOS also have insulin resistance and hyperinsulinaemia, which may contribute to the clinical and endocrine abnormalities. The aetiology of PCOS is not clear but studies in the Rhesus monkey suggest that exposure to excess androgen during intrauterine life results in many of the features of human PCOS, including ovarian dysfunction, abnormal LH secretion and insulin resistance.

OBJECTIVE

To review the studies from the literature, including those of the author, regarding aetiology, presentation and management of PCOS in adolescents.

RESULTS AND CONCLUSIONS

We have proposed that PCOS in adolescents arises as a result of a genetically determined disorder of ovarian function that results in hyper-secretion of androgens, possibly during fetal life and also during physiological activation of the hypothalamic-pituitary-ovarian in infancy and at the onset of puberty. There is plentiful evidence for a genetic basis for PCOS (it appears to be a complex endocrine disorder resulting from the effects of a several genes), but environmental factors, notably nutrition, influence the clinical and biochemical phenotype. Obesity unmasks or amplifies symptoms, endocrine and metabolic abnormalities. The increasing incidence of childhood obesity has resulted in an alarming Increase not only in distressing symptoms but also impaired glucose tolerance and even diabetes among adolescent girls with PCOS. The search for PCOS genes in this condition, that is not only heterogeneous but also presents only in women of reproductive age, is not straightforward and has produced few convincing candidates so far. In due course, however, identification of the major susceptibility loci is likely to provide key insight into the aetiology of the syndrome and improve diagnosis and management.

Changes in serum leptin, insulin, androstenedione and luteinizing hormone during ovarian cycle in the bat, Taphozous longimanus

Detailed reproductive pattern and associated endocrine characteristics have been documented in only a few species of order Chiroptera. The aim of the present study was to examine the changes in body weight, serum insulin, leptin, androstenedione and luteinizing hormone (LH) concentrations during annual ovarian cycle in the sheath-tailed bat, Taphozous longimanus. Bats were sampled over three years. Leptin, a satiety hormone produced primarily by adipose tissue, provides information to feeding center of the brain about nutritional status, fat mass, appetite and energy expenditure. The circulating concentration of leptin begins to increase from October and attains a peak in December. The peak serum leptin concentration coincides with body weight in November before winter dormancy in December. The serum leptin levels dissociate from body weight during December. The other peaks of serum leptin levels coincide with late stages of the two successive pregnancies. The serum insulin concentration begins to increase from September and attains a peak during December. The insulin concentration remains low from January to August. The circulating androstenedione concentration begins to increase in October, reaching a peak in December. This increase in androstenedione concentration correlated with the period of heavy accumulation of abdominal fat and increase in body weight. There was a sharp decline in androstenedione concentration and body weight in January. The serum LH shows peaks, in November, coinciding with the peaked body weight, the other peaks in January and May, coinciding with ovulation for the two successive pregnancies. The high leptin and insulin levels might be responsible for the maintenance of reproductive response and gonadal function during adverse environmental condition in the winter, while high androstenedione, and associated body weight along with LH might be responsible for maintaining basal gonadal function. We conclude that high leptin, androstenedione and insulin serve, as signal for the reproductive functions in that sufficient body fat are available to meet the caloric demands and maintain normal function during adverse winter conditions.

Effect of antiepileptic drugs on reproductive endocrine function in individuals with epilepsy

It is well known that epilepsy, antiepileptic drugs (AEDs), and the reproductive system have complex interactions. Fertility is lower in both men and women with epilepsy than in the general population. Moreover, reproductive endocrine disorders are more common among patients with epilepsy than among the population in general. These disorders have been attributed both to epilepsy itself and to use of AEDs. The use of the liver enzyme-inducing AEDs phenobarbital, phenytoin and carbamazepine increases serum sex hormone-binding globulin (SHBG) concentrations in both men and women with epilepsy. Over time, the increase in serum SHBG levels leads to diminished bioactivity of testosterone and estradiol, which may result in diminished potency in men and menstrual disorders in some women, and thus to reduced fertility. Liver enzyme-inducing AEDs also reduce the efficacy of oral contraceptives. Valproic acid medication may have effects on serum androgen concentrations and it reduces serum follicle stimulating hormone levels in men with epilepsy. However, the clinical significance of valproic acid-related reproductive endocrine changes in men is unknown. On the other hand, in women, use of valproic acid appears to be associated with a frequent occurrence of reproductive endocrine disorders characterised by polycystic changes in the ovaries, high serum testosterone concentrations (hyperandrogenism) and menstrual disorders. These disorders are especially common among women who have gained weight during valproic acid treatment. There are some discrepancies regarding the reported occurrence of reproductive endocrine disorders in women taking valproic acid for epilepsy. However, most studies also including patients receiving valproic acid for other reasons than epilepsy, and studies in different non-epileptic animal models, have shown an association between valproic acid medication and hyperandrogenism and related reproductive endocrine disorders. From a practical point of view, the length of the menstrual cycles and bodyweight should be monitored in women with epilepsy after commencement of treatment with valproic acid. A serum testosterone assay is helpful in following the possible biochemical endocrine changes. Ultrasonography of the ovaries (preferably transvaginal) is indicated if clinical assessment and serum testosterone measurement imply that there is a clinically significant valproic acid-related reproductive endocrine problem. That would be the case if the menstrual cycles were irregular or prolonged (usually >35 days) and serum testosterone levels elevated, especially with associated weight gain. The endocrine effects of the new AEDs have not been widely studied. However, it seems they may offer an alternative if reproductive endocrine problems emerge during treatment with the older AEDs.

Insulin-lowering agents in the management of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a medical condition that has brought multiple specialists together. Gynecologists, endocrinologists, cardiologists, pediatricians, and dermatologists are all concerned with PCOS patients and share research data and design clinical trials to learn more about the syndrome. Insulin resistance is a common feature of PCOS and is more marked in obese women, suggesting that PCOS and obesity have a synergistic effect on the magnitude of the insulin disorder. Hyperinsulinemia associated with insulin resistance has been causally linked to all features of the syndrome, such as hyperandrogenism, reproductive disorders, acne, hirsutism, and metabolic disturbances. Women with PCOS should be evaluated for cardiovascular risk factors, such as lipid profile and blood pressure. Modification of diet and lifestyle should be suggested to those who are obese. Several insulin-lowering agents have been tested in the management of PCOS. In particular, metformin is the only drug currently in widespread clinical use for treatment of PCOS. In a high percentage of patients, treatment with metformin is followed by regularization of menstrual cycle, reduction in hyperandrogenism and in cardiovascular risk factors, and improvement in response to therapies for induction of ovulation.

Decreased total antioxidant status and increased oxidative stress in women with polycystic ovary syndrome may contribute to the risk of cardiovascular disease

OBJECTIVE

To determine oxidative stress by the level of protein carbonyls and total antioxidant status (TAOS), and whether oxidative stress is associated with increased risk of cardiovascular disease in women with polycystic ovary syndrome (PCOS).

DESIGN

Controlled clinical study.

SETTING

University hospital.

PATIENT(S)

Thirty women with PCOS and 31 healthy control women.

INTERVENTION(S)

Biometric measures and blood samples collection.

MAIN OUTCOME MEASURE(S)

C-reactive protein (CRP), lipid fractions, glucose, protein carbonyls, insulin, and other hormone (gonadotropins, androgens) levels and TAOS were measured. The estimate of insulin resistance was calculated by homeostasis model assessment (HOMA-R).

RESULT(S)

The women with PCOS had significantly higher serum fasting insulin, CRP, protein carbonyl levels, HOMA-R, LH levels, and LH/FSH ratios than healthy women. However, TAOS was significantly lower in women with PCOS. TAOS was negatively correlated with fasting insulin, HOMA-R, CRP, and protein carbonyls. Fasting insulin was positively correlated with protein carbonyls. High density lipoprotein (HDL) was inversely associated with fasting insulin, HOMA-R, and protein carbonyls.

CONCLUSION(S)

Increased oxidative stress and decreased antioxidant capacity may contribute to the increased risk of cardiovascular disease in women with PCOS, in addition to known risk factors such as insulin resistance, hypertension, central obesity, and dyslipidemia.

Relationship between corticosterone and body weight, androstenedione and insulin during the period of delayed ovulation in a vespertilionid bat, Scotophilus heathi

The aim of the present study was to evaluate the relationship between corticosterone, body weight, insulin and androstenedione in order to understand the role of adrenal in contributing hyperandrogenism during delayed ovulation in S. heathi. The circulating corticosterone concentration in female S. heathi showed significant seasonal variation. The peak corticosterone concentration observed during August-September coincides with increased feeding activities in S. heathi. The present study noted a seasonal variation in relationship of corticosterone with insulin and androstenedione in S. heathi. An inverse relationship of corticosterone with insulin and androstenedione was found during August to December, but not during January to May. A seasonal variation in the effect of adrenocorticotropic hormone (ACTH) on adrenal corticosterone production in vitro was observed during reproductive cycle. Corticosterone production in vitro by adrenal declined significantly as compared to the control during quiescence in September. The finding suggests that adrenal attained the peak responsiveness to ACTH during September. ACTH significantly enhanced the androstenedione production by the adrenal in vitro during December, when the circulating androstenedione was also high in S. heathi. This suggests that the adrenal may also contribute to hyperandrogenism during the period of delayed ovulation in S. heathi. Further studies are required to reveal the unique pattern of seasonal relationship between corticosterone, insulin and androstenedione in S. heathi.

Fasting serum insulin and lipid levels in men with epilepsy

BACKGROUND

Previous studies suggest that obese women taking valproate (VPA) for epilepsy are insulin resistant.

OBJECTIVE

To assess the effects of antiepileptic drugs on serum insulin and lipid levels in men with epilepsy.

METHODS

Body mass index (BMI) and fasting serum concentrations of insulin and lipids were measured in 102 men with epilepsy who were treated with VPA, carbamazepine (CBZ), or oxcarbazepine (OXC) monotherapy. Thirty-two healthy men served as control subjects.

RESULTS

Obesity was not more common among VPA-treated men than among other men with epilepsy or the control subjects. However, the obese VPA-treated men had higher serum insulin levels (p < 0.001) than the obese control subjects despite similar BMI. CBZ and OXC did not have any significant effect on any of the measurements. Fasting serum insulin concentrations above the normal range were observed in seven obese VPA-treated patients (35%) but in only one obese control subject (5%). Five obese VPA-treated patients (25%) and one obese control subject (5%) had serum triglyceride levels above the normal range, and a low high-density lipoprotein/total cholesterol ratio was observed in two obese VPA-treated patients (10%).

CONCLUSIONS

Obese valproate-treated men have high serum insulin levels, indicating insulin resistance. Moreover, some of the valproate-treated men cluster cardiovascular risk factors such as obesity, hyperinsulinemia, and elevated serum triglyceride concentrations. CBZ and OXC do not seem to have any significant effects on serum insulin or lipid levels in men with epilepsy.

Hyperinsulinaemia and polycystic ovary syndrome

Over the past 20 years, it has been established that hyperinsulinaemia is a fundamental disturbance in many women with polycystic ovary syndrome (PCOS). A subgroup of women with this syndrome have 'metabolic PCOS' which can be considered to be a pre-diabetic state. Clinically, this subgroup is most easily identified in obese women with a strong family history of diabetes in whom menstrual disturbance is the predominant feature. There is an urgent need to define the more subtle features in young lean women with PCOS, in whom the metabolic syndrome is yet to emerge, which would enable the prediction of future health risks. The molecular mechanisms of insulin resistance leading to hyperinsulinaemia are now being elucidated. Abnormalities of both insulin secretion and intracellular insulin signalling have both been proposed in women with PCOS. Strategies to lower serum insulin concentrations include diet, exercise and possibly, oral insulin sensitizing agents such as metformin. Although the short-term efficacy of reducing hyperinsulinaemia in women with PCOS is clear, the best method to prevent the progression to diabetes later in life has not been defined.

Altered ovarian function and cardiovascular risk factors in valproate-treated women

PURPOSE

Polycystic ovaries and menstrual disturbances seem to be common among women taking valproate for epilepsy. The purpose of the present study was to assess the frequency of valproate-related metabolic and endocrine disorders in different groups of women with epilepsy.

SUBJECTS AND METHODS

Seventy-two women with epilepsy and 52 control subjects from centers in three European countries (Finland, Norway, and the Netherlands) participated in the study. Thirty-seven of the women with epilepsy were taking valproate monotherapy and 35 carbamazepine monotherapy.

RESULTS

The frequency of polycystic ovaries or hyperandrogenism, or both, among valproate-treated women with epilepsy was 70% (26 of 37) compared with 19% (10 of 52) among control subjects (P <0.001). They were found in 79% (11 of 14) of obese and 65% (15 of 23) of lean women on valproate, and in 20% (7 of 35) of carbamazepine-treated women. The obese valproate-treated women with polycystic ovaries or hyperandrogenism, or both, had hyperinsulinemia and associated unfavorable changes in serum lipid levels consistent with insulin resistance.

CONCLUSIONS

Polycystic ovaries and related hyperandrogenism are frequently encountered in both obese and lean women taking valproate for epilepsy. The use of valproate is associated with risk factors for cardiovascular disease in obese women.

Early hormonal changes during valproate or carbamazepine treatment: a 3-month study

BACKGROUND

Long-term treatment with valproate (VPA) or carbamazepine (CBZ) may induce reproductive endocrine disorders in patients with epilepsy.

METHODS

Serum concentrations of reproductive hormones were studied in 17 women and 22 men with recently diagnosed epilepsy before they started either VPA or CBZ medication, and 1 and 3 months later.

RESULTS

No weight gain or clinical signs of hormonal disorders were observed during the follow-up. The mean serum levels of testosterone, luteinizing hormone, follicle-stimulating hormone, and sex hormone-binding globulin (SHBG) increased, and dehydroepiandrosterone sulfate (DHEAS) decreased, in women starting VPA. Serum testosterone levels increased in half of the women on VPA. Serum concentrations of progesterone and dehydroepiandrosterone increased, and gonadotropins decreased, in men on VPA during the follow-up. Serum SHBG levels increased and DHEAS decreased during the first months of CBZ treatment in both sexes. In addition, the free-androgen index decreased in men after starting CBZ.

CONCLUSIONS

Hormonal changes occur after only 1 month's use of VPA or CBZ. VPA-treatment seems to be associated with increased serum androgen levels, but the profile of hormonal changes appears to be different in women than in men. The use of CBZ, in turn, was associated with increased SHBG concentrations and thus with diminished sex steroid function in both sexes. The women with increased serum testosterone levels in the early phase of VPA medication may be at increased risk for VPA-related endocrine disorders later during treatment.

Hormone profiles in young adults with epilepsy treated with sodium valproate or lamotrigine monotherapy

PURPOSE

Treatment with sodium valproate (VPA) may be associated with polycystic ovarian syndrome (PCOS) in some women with epilepsy. By comparing hormone profiles in young adults taking VPA or lamotrigine (LTG) as monotherapy, this study aimed to explore whether a pharmacologic effect of VPA could be responsible for this observation.

METHODS

Hormone profiles in men and women taking VPA (n = 40) or LTG (n = 36) monotherapy for epilepsy were compared. None of the women were receiving hormonal contraception or replacement. Patients gave details of seizure type and frequency, menstrual cycle, and medical and drug history. Body mass index was calculated, and fasting insulin, glucose, cholesterol, triglycerides (TG), high- and low-density lipoproteins, testosterone, dihydroepiandosterone (DHEA), androstenedione, sex hormone-binding globulin (SHBG), free androgen index (FAI), luteinising hormone (LH), follicle-stimulating hormone (FSH), and antiepileptic drug (AED) concentrations were measured.

RESULTS

There were no differences between treatment groups for both sexes in age and seizure control. Only four obese VPA-treated women were hyperinsulinaemic (p = 0.05); three with abnormal menstrual cycles; one with raised testosterone. Testosterone (p = 0.02), FAI (p = 0.03), and TG (p = 0.02) levels were higher, however, in women taking the drug. Obese patients of both sexes (p = 0.01) and VPA-treated men (p = 0.03) had higher insulin concentrations.

CONCLUSIONS

VPA therapy may be associated with subclinical elevation in fasting insulin levels. Testosterone and TG levels were higher in VPA-treated women compared with the levels in those taking LTG. However, only a minority of obese females exhibited biochemical characteristics suggestive of PCOS. Biochemical screening may allow women at risk of developing PCOS to avoid VPA.

How common are polycystic ovaries and the polycystic ovarian syndrome in women with Cushing's syndrome?

OBJECTIVE

Women with Cushing's syndrome (CS) may present with menstrual irregularity and symptoms/signs of hyperandrogenism, a phenotype similar to that of the polycystic ovarian syndrome (PCOS); however, currently there are no data on the prevalence of either polycystic ovaries (PCO) and/or PCOS in patients with CS. The aim of this study was to investigate their presence among women of reproductive age presenting with CS by analysing clinical, endocrinological and ultrasonographic features.

DESIGN

Prospective study of all women within the reproductive age (range 18-40 years) who presented with CS between August 1994 and January 2000.

SUBJECTS AND METHODS

Thirteen women (median age 32 years, range 18-39 years) with CS were evaluated. The diagnosis of CS was based on the presence of appropriate clinical features and an elevated serum midnight cortisol with failure to suppress 0900 hours serum cortisol to less than 50 nmol/l following a formal low-dose dexamethasone suppression test (LDDST). All women had their clinical features relevant to possible hyperandrogenism, menstrual disorder and infertility recorded, and circulating gonadotrophins, oestradiol, androgens and SHBG levels measured; ovarian ultrasonography was performed during their initial assessment. Relevant MR/CT imaging of the pituitary and/or adrenal glands was performed.

RESULTS

Eleven women had ACTH-dependent CS [nine Cushing's disease (CD), one ectopic ACTH syndrome due to a bronchial carcinoid, one periodic CS of unknown origin); two patients had ACTH-independent CS (adrenal adenomas). All women with CS had at least one symptom/sign of hyperandrogenism (13 hirsutism, seven acne, five male-pattern alopecia). Nine women (70%) had menstrual disturbances (four oligomenorrhoea, four amenorrhoea, one polymenorrhoea) while four women (30%) had a normal menstrual pattern. Serum oestradiol levels for the group as a whole were similar to those observed in the early follicular phase of normally menstruating women; however, seven women had low oestradiol, LH and FSH levels suggestive of hypogonadotrophic hypogonadism. Serum androgen levels (testosterone, androstendione and DHEAS), even in the presence of symptoms/signs of hyperandrogenism, were within the normal reference range but SHBG levels were uniformly decreased even in women with normal menstrual cycles. There was a negative correlation between urinary free cortisol, but not mean serum cortisol, and serum oestradiol, testosterone and SHBG levels (r = - 0.8, r = - 0.86 and r = - 0.66, P<0.02, P<0.01 and P<0.05, respectively), but not LH or FSH levels. Despite the fact that seven of these 13 patients lacked normal gonadotrophin stimulation, ovarian volumes of both ovaries were relatively preserved: right 7.3 ml, range 2.8-12.8 ml, and left 5.3 ml, range 2.3-13 ml. Women who were defined as oestrogen sufficient (E2 > 140 pmol/l) had higher serum androstenedione, and lower urinary free cortisol levels, than women who were oestrogen deficient (E2 < 140 pmol/l). Six of the 13 women (46%) had ovarian morphology suggestive of PCO, four of six oestrogen sufficient women and two of seven oestrogen deficient women. The results did not differ according to the underlying cause of CS.

CONCLUSIONS

PCO and PCOS are common in women with Cushing's syndrome; women with Cushing's syndrome and only moderately elevated cortisol secretion maintain gonadotrophin stimulation to the ovary with normal oestradiol levels, in contrast to women with Cushing's syndrome and higher cortisol secretion who develop hypogonadotrophic hypogonadism. However, even in the latter group, high ovarian volumes were maintained and some had ovarian morphology suggestive of PCO.

Clinical presentation of PCOS following development of an insulinoma: case report

A 24 year old woman presented with a prolonged clinical history of fasting and exertional hypoglycaemia, and was subsequently diagnosed with an insulinoma. Concurrent symptoms of oligomenorrhoea and hyperandrogenism of similar duration were noted. Biochemically, hyperinsulinaemia was observed in association with a raised serum luteinizing hormone (LH), raised testosterone and androstendione concentrations. Surgical removal of the insulinoma resulted in resolution of the clinical and biochemical features of the polycystic ovarian syndrome (PCOS) but minimal change was observed in the ovarian ultrasound appearances. This case demonstrates the role of insulin in mediating the hypersecretion of both LH and androgens in women with polycystic ovaries. We suggest that hyperinsulinaemia converted occult 'polycystic ovaries' to become clinically manifest as 'polycystic ovary syndrome'. This paradigm has clear implications for women with insulin dependent diabetes mellitus who presumably have systemic hyperinsulinaemia.

Alterations in cardiac flow parameters in patients with polycystic ovarian syndrome

The aim of this study was to examine the echocardiographic profiles of patients with polycystic ovarian syndrome (PCOS). Serum concentrations of follicle stimulating hormone, luteinizing hormone, androstenedione, free testosterone, prolactin, DHEA-SO(4) and 17-OH-progesterone, lipid profile (high and low density lipoproteins, triglyceride and total cholesterol) and basal and total insulin after a glucose tolerance test were measured in 35 patients with PCOS and 35 healthy controls matched for body mass index. Doppler, two dimensional M mode echocardiography was performed for the following indices: isovolumetric relaxation time (IVRT), E wave duration time (EVT), A wave duration time (AVT), E wave deceleration time (DT), peak early diastolic flow velocity (PEV), peak late diastolic flow velocity (PAV), E wave velocity time integral (FVI-E), A wave velocity time integral (FVI-A), atrial filling fraction (AFF), ejection fraction (EF), pre-ejection time (PEP), ejection time (ET) and aortic flow velocity time integral (FVI). Androstenedione, free testosterone, low density lipoproteins and cholesterol concentrations were significantly higher in patients with PCOS. There was no difference in basal and total insulin concentrations. IVRT, AVT, FVI-A, AFF, and PEP were higher in patients with PCOS, while PEV, FVI-E, EF, ET, EVT and EVT/AVT were higher in the control group. There was a positive correlation between basal insulin values and IVRT, and between total insulin values and EF. These changes are consistent with a non-restrictive type of diastolic dysfunction and left ventricular stiffness. PCOS may lead to diastolic dysfunction via hyperinsulinaemia and male type dyslipidaemia.

Changes in circulating insulin and corticosterone concentrations during different reproductive phases and their relationships to body weight and androstenedione concentration of male Scotophilus heathi

The aim of the present study was to determine the serum levels of insulin and corticosterone during different reproductive stages in a natural population of the male bat, Scotophilus heathi and their relationship to body weight and androstenedione level. Changes in body weight were marked by weight gain before winter dormancy and weight loss during winter dormancy. Circulating insulin level varied significantly over the season and correlated positively with changes in body weight and androstenedione level. Circulating corticosterone level also varied significantly over the season but correlated negatively with changes in body weight and androstenedione level. High corticosterone level during August coincided with a period of increased feeding activity in this species. The results suggest that insulin may act as an anabolic agent to promote fat deposition and corticosterone exerts a predominantly fat-mobilizing influence. A high insulin level prior to winter dormancy may be an important factor responsible for inducing high androstenedione concentration shown in Scotophilus heathi.

Metformin therapy improves the menstrual pattern with minimal endocrine and metabolic effects in women with polycystic ovary syndrome

OBJECTIVE

To determine the clinical, hormonal, and biochemical effects of 4-6 months of metformin therapy in obese patients with polycystic ovary syndrome (PCOS).

DESIGN

Prospective study.

SETTING

The Gynecological Endocrine Unit of University Central Hospital, Oulu, Finland.

PATIENT(S)

Twenty obese patients with PCOS.

INTERVENTION(S)

Patients were treated with 0.5 g of metformin three times daily for 4-6 months.

MAIN OUTCOME MEASURE(S)

Clinical symptoms, menstrual pattern, and hirsutism, as well as serum concentrations of sex steroids, sex hormone-binding globulin (SHBG), gonadotropins, and lipids were assessed during the treatment.

RESULT(S)

Eleven women (68.8% of the women with menstrual disturbances) experienced more regular cycles during therapy. No changes in hirsutism, body mass index, or blood pressure occurred. The mean testosterone level was decreased significantly after 2 months of treatment but returned to the starting level by 4-6 months. Free testosterone levels decreased significantly during the treatment. There was no significant change in the levels of other sex steroids or lipids measured at 4-6 months of treatment.

CONCLUSION(S)

Metformin therapy is well tolerated by the majority of patients and may be clinically useful, especially in obese patients with PCOS and menstrual disturbances.

Valproate, lamotrigine, and insulin-mediated risks in women with epilepsy

We recently reported the frequent occurrence of polycystic ovaries and hyperandrogenism associated with weight gain and hyperinsulinemia in women taking valproate for epilepsy. The purpose of this study was to evaluate the risks related to valproate-induced hyperinsulinemia and their reversibility after discontinuing the medication. Sixteen women with valproate-related polycystic ovaries or hyperandrogenism participated in the study. Vaginal ultrasonography was performed, and endocrine and lipid parameters were measured. Thereafter, lamotrigine was substituted for valproate and the patients were observed for 12 months. Twenty-four healthy age-matched women served as control subjects. Twelve women completed the 12-month follow-up. While still on valproate they had centripetal obesity with associated hyperinsulinemia and unfavorable serum lipid profiles. The body-mass index and fasting serum insulin and testosterone concentrations decreased during the first year after replacing valproate with lamotrigine whereas the HDL-cholesterol/total cholesterol ratios increased from 0.17 +/- 0.06 to 0.26 +/- 0.05. The total number of polycystic ovaries in these women decreased from 20 during valproate medication to 11 one year after replacing valproate with lamotrigine. Valproate induces a metabolic syndrome with centripetal obesity, hyperinsulinemia, lipid abnormalities, and polycystic ovaries/hyperandrogenism in women with epilepsy. These valproate-related risks can be reduced by substituting lamotrigine for valproate.

Treatment of androgen excess in females: yesterday, today and tomorrow

Hirsutism, acne and androgenic alopecia represent, in females, some of the manifestations of the clinical spectrum of hyperandrogenism. These pictures represent not only cosmetic damage, but also a source of remarkable psychological distress. Often hirsutism is regarded as presumptive evidence of a lack of femininity. The major diagnostic concern is to exclude an ovarian or adrenal androgen-secreting tumor, a congenital hyperplasia or polycystic ovary disease. Ethnic background should be taken into account together with the progression of the symptoms. Following the etiology, surgery and exogenous glucocorticoids or inhibition of gonadotropin secretion have to be carefully chosen in the management of different kinds of hyperandrogenism. Several pharmacologic agents have recently shown the ability to block the androgen receptors at target organ sites, thus allowing a specific antiandrogenic treatment. In some cases cosmetic measures could be of great value. Obesity accompanied by hyperinsulinemia can represent the main cause of ovary androgen hypersecretion; therefore a reduced body weight and muscle activity represent the basis of any treatment. Some other drugs, such as long-acting analogs of somatostatin, could be considered among possible drugs for the future. The aim of this article is to provide an appraisal of what is presently known about the regulation of hair growth, the various causes of excessive androgen secretion and the current methods to solve, safely, this important feminine clinical problem.

Current concepts of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) may be loosely defined as unexplained hyperandrogenism, with variable degrees of cutaneous symptoms, anovulatory symptoms, and obesity. The vast majority of patients with the full-blown Stein-Leventhal syndrome have functional ovarian hyperandrogenism (FOH). However, FOH often occurs without the LH excess or polycystic ovaries of classic PCOS. Functional adrenal hyperandrogenism (FAH) is often found in the syndrome, but it is less closely associated with anovulatory symptoms than is FOH. The vast majority of FOH seems to arise from abnormal regulation (dysregulation) of ovarian androgen secretion. This typically is due to escape from desensitization to luteinizing hormone (LH); this appears to occur because of a breakdown in the processes that normally coordinate ovarian androgen and oestrogen secretion so as to prevent hyperoestrogenism. Similar dysregulation of adrenal androgen secretion in response to ACTH seems to account for most FAH. Dysregulation of androgen secretion may affect the ovary alone (isolated FOH), the adrenal alone (isolated FAH), or both together. Modest insulin resistance is common in PCOS/FOH, and the resultant hyperinsulinaemia is a major candidate as the cause of the dysregulation. The hyperinsulinaemia may arise from either 'nature' (genetic defects) or 'nurture' (exogenous obesity). Although hyperinsulinaemia alone does not have an obvious effect on steroidogenesis, it may act in genetically predisposed women as a 'second hit' to unmask latent abnormalities in steroidogenesis. The ovary, the adrenal cortex, and several other organs paradoxically function as if responding to the hyperinsulinaemic state in spite of resistance to the effects of insulin on glucose metabolism. PCOS should be viewed as an early manifestation of a hyperinsulinaemic condition that will predispose to cardiovascular and metabolic complications later in life. A subset of PCOS patients appear to have not only insulin resistance but also beta-cell secretory dysfunction, which may indicate a relationship of the disorder to NIDDM. The fundamental genetic defects remain to be elucidated.

Polycystic ovary syndrome: the present position

This article discusses two areas that have seen progress in our understanding and management of women with polycystic ovary syndrome. The first relates to factors responsible for clinical expression of the disorder, the second to the management of infertility by surgical methods. These two areas have been chosen partly because of their intrinsic importance and partly because they indicate the breadth of work being pursued by investigators and clinicians in this field.

Hyperinsulinemia in the polycystic ovary syndrome: a clinical, endocrine and echographic study in 240 patients

In recent years numerous studies have suggested insulin to be an important regulator of ovarian function and hyperinsulinemia to be associated with hyperandrogenism. An oral glucose-tolerance test was carried out in 240 women with polycystic ovary syndrome and, based on its result, 142 of the women (59.2%) were insulin resistant or hyperinsulinemic and 98 (40.8%) were normoinsulinemic. Compared with the normoinsulinemic group, the hyperinsulinemic group had a greater incidence of obesity (52.8 vs. 21.4%), secondary amenorrhea (24.6 vs. 9.2%), androgenic symptoms (85.9 vs. 67.4%) and, in particular, hirsutism with or without acne (71.8 vs. 48.0%). Moreover, the hyperinsulinemic group had significantly higher plasma levels of androstenedione, testosterone, free testosterone and insulin, and lower levels of luteinizing hormone, estradiol and sex hormone-binding globulin.

The entero-insular axis in polycystic ovarian syndrome

We investigated the contributions made by the entero-insular axis, proinsulin and the fractional hepatic extraction of insulin to the hyperinsulinaemia characteristic of polycystic ovarian syndrome (PCOS). We measured plasma glucose, gastric inhibitory polypeptide (GIP), glucagon-like peptide-1 (7-36 amide) (GLP-1(7-36) amide), immunoreactive insulin (IRI), intact proinsulin (IPI), and C-peptide concentrations during a 75 g oral glucose tolerance test in seven normal weight women with PCOS and eight healthy women. Women with PCOS had higher fasting (P = 0.05) and integrated (P < 0.01) IRI concentrations than controls. Fasting C-peptide levels were similar in both groups but integrated C-peptide (P < 0.05) concentrations were greater in PCOS subjects than controls. Fasting and integrated concentrations of glucose, GIP and GLP-1(7-36) amide were similar in subjects with PCOS and controls. Although fasting IPI concentrations were similar in both groups, integrated IPI concentrations were higher (P = 0.05) in patients with PCOS. Women with PCOS had similar fasting but higher (P < 0.05) integrated IRI:C-peptide molar ratios than controls. Fasting and integrated IPI:IRI molar ratios were similar in both groups. These results confirm that lean women with PCOS have peripheral hyperinsulinaemia. The mild fasting hyperinsulinaemia is due to increased pancreatic secretion, whereas the stimulated hyperinsulinaemia is due to both pancreatic hypersecretion and reduced fractional hepatic extraction of insulin. Hyperproinsulinaemia is modest and appropriate in PCOS, GIP and GLP-1(7-36) amide do not contribute to the stimulated hyperinsulinaemia in PCOS.

Polycystic ovary syndrome: clinical aspects

The clinical presentation of PCOS is likely to be the end process of many pathogenic mechanisms, the definition of which is only now beginning to be unravelled. While the application of ultrasonography to the diagnosis of PCOS has undoubtedly added greatly to our understanding of the breadth of the disorder and our appreciation of its heterogeneity, careful distinction has to be made between polycystic ovaries and polycystic ovary syndrome in order to define optimal treatments, particularly in women with menstrual disturbance. In the presence of obesity, no treatment regimen can neglect weight reduction as the main thrust of intervention, no matter whether the goal be to improve hirsutism or infertility.

The impact of obesity on hormonal parameters in hirsute and nonhirsute women

The influence of obesity on sex hormone-binding globulin (SHBG) and androgen concentrations in hirsute and nonhirsute women has been evaluated. The study was performed in 226 hirsute women (88 obese and 138 non-obese) classified as being affected by polycystic ovarian syndrome (PCOS) or by idiopathic hirsutism (IH) and in 100 nonhirsute control women ([C] 60 lean and 40 obese). SHBG, free testosterone (fT), androstenedione (A), estradiol (E2), dehydroepiandrosterone sulfate (DHEAS), and gonadotropin levels were measured during the first week of the menstrual cycle by radioimmunoassay (RIA). A significant negative correlation between SHBG and body mass index (BMI) was observed in PCOS, IH, and C women. In obese women--whether PCOS, IH, or C-fT levels were significantly higher and, conversely, SHBG levels were lower than in non-obese women. A negative correlation between SHBG and fT was evidenced in each group. Upper-body obesity was associated with lower SHBG and higher fT levels than lower-body obesity. In conclusion, obesity, particularly upper-body obesity, is associated with a reduction in SHBG and an increase in fT in both nonhirsute and hirsute women.

Cardiac flow velocity in women with the polycystic ovary syndrome

OBJECTIVE

Women with the polycystic ovary syndrome (PCOS) often have several of the known risk factors for cardiovascular disease, including hyperinsulinaemia. We have therefore investigated variables of cardiac flow in young women with PCOS and related them to blood levels of reproductive hormones (LH, FSH, oestradiol and testosterone) and also of insulin.

DESIGN

A prospective study.

PATIENTS

Twenty-six young women with PCOS (mean age 22.8 +/- 0.9 years; mean BMI 23.0 +/- 0.8) and 11 healthy age matched women with regular ovulatory cycles (mean age 26.3 +/- 1.7 years; mean BMI 22.9 +/- 0.9).

MEASUREMENTS

Cardiac flow was measured by pulsed wave Doppler echocardiography in the follicular phase of the cycle in controls and oligomenorrhoeic women; there was no special timing for amenorrhoeic women. The indicators assessed were: ejection fraction (EF), pre-ejection time (PEP), ejection time (ET), peak systolic flow velocity (PFV), acceleration time (AT), flow velocity integral (FVI), mean acceleration (MA), diastolic time (DT), early diastolic filling time (Ei), atrial filling time interval (Ai), peak velocity of the early diastolic filling (PE) and peak velocity of the atrial filling (PA). Serum LH, FSH, oestradiol, testosterone, SHBG and insulin concentrations were analysed by standard RIA.

RESULTS

Significantly lower PFV (1.055 +/- 0.025 vs 1.242 +/- 0.054, P = 0.0006) and MA (17.06 +/- 0.57 vs 23.00 +/- 1.49, P = 0.0001) and longer AT (0.063 +/- 0.001 vs 0.056 +/- 0.004, P = 0.026) were found in women with PCOS as compared to age matched controls. Significant negative correlation between serum fasting insulin concentration and EF (r = -0.725, P = 0.002), PFV (r = -0.719, P = 0.0025), FVI (r = -0.654, P = 0.008) and MA (r = -0.757, P = 0.001) was observed in the 15 women with PCOS in whom insulin was measured.

CONCLUSION

An inverse relation between serum fasting insulin level and left ventricular systolic outflow parameters suggests that insulin is associated with the decreased systolic flow velocity observed in women with PCOS.

Prolonged treatment of hirsutism with flutamide alone in patients affected by polycystic ovary syndrome

Hirsutism is a common symptom of women affected by polycystic ovary syndrome (PCOS). The effectiveness of the antiandrogen flutamide alone was studied in 25 patients affected by PCOS with severe hirsutism for a period of 24 months. Seventeen of these patients had not been treated before and eight had had previous but unsatisfactory therapy. Nineteen patients showed a normal body weight (BMI < 25 kg/m2) whereas six were obese (BMI > 35 kg/m2). A chemical and endocrinological evaluation and an assessment of the degree of hirsutism, assigned by Ferriman-Gallwey score (mean 22 +/- 3.038), was performed under baseline conditions. Patients started treatment with flutamide (Eulexin, Schering-Plough, Kenilworth, USA) at the dose of 500 mg daily. A chronobiological assessment of gonadotropin episodic secretion and of gonadotropin response to GnRH challenge (10 micrograms in bolus) was done before and on day 7 of flutamide administration. During treatment, our patients showed a marked and significant reduction of hirsutism starting from a score of 6 and reaching the maximum (9.6 + 2.1) at 24 months of therapy. No relevant hormonal changes or side-effects were observed during therapy. Our data demonstrate that hirsutism in PCOS can rapidly and markedly respond to treatment with flutamide alone without important side-effects even if administered for a long period.

Timing of weight gain in relation to breast cancer risk

Excessive weight gain in women at the time of intense hormonal change can result in metabolic dysfunction. The metabolic/endocrine effect of puberty, pregnancy or menopause on breast tissue 'aging' is likely to be more relevant to a woman's breast cancer risk than is her degree of obesity at the time when the cancer presents. Experimental evidence suggests that the susceptibility of mammary tissue to carcinogenesis is greatest in early adult life, and multiple studies show that a history of weight gain in early adult life is associated with increased breast cancer risk in Western women. Excessive weight gain in that age group is associated with the development of hyperinsulinaemia in individuals with genetic susceptibility to insulin resistance. The insulin resistance syndrome may be a metabolic link between weight gain and breast cancer risk in Western women. Some studies suggest that in postmenopausal women, hyperinsulinaemia is related more to overall obesity, whereas in premenopausal women it is related more to abdominal localisation of fat. This may explain why an increased body mass index is a risk marker for breast cancer in postmenopausal but not premenopausal women. (A premenopausal woman with an average body mass index may have a large intra-abdominal fat mass associated with the presence of hyperinsulinaemia.) It is hypothesised that over-nutrition and inadequate physical exercise favour the development of hyperinsulinaemia and also increase breast cancer risk in women with a genetic susceptibility to both conditions. The hypothesis can be tested by specific intervention studies.