Endocrine and metabolic effects of octreotide, a somatostatin analogue, in lean PCOS patients with either hyperinsulinaemia or lean normoinsulinaemia

Evaluation of serum anti-nuclear antibody among women with PCOS: a hospital based single center cross sectional study

Polycystic ovary syndrome (PCOS), a major endocrinopathy is associated with barrage of metabolic aberrations. Reports in literature on association of PCOS and autoimmunity are conflicting. We aim to evaluate serum levels of anti-nuclear antibody (ANA) among Indian women with PCOS. In this hospital-based single center cross-sectional study, women qualifying a diagnosis of PCOS by Rotterdam criteria 2003 were recruited. Eighty-nine eligible women who consented were enrolled. All these women along with 87 age-matched, healthy controls underwent, clinical (menstrual history, anthropometry, hirsutism scoring), biochemical, hormonal assessment and serum ANA estimation. OGTT after overnight (8-12 h) fast with 75 g oral glucose load was done for 1 h, 2 h glucose and insulin measurements. The mean age of cases and controls was comparable (22.67 ± 5.53 vs. 22.84 ± 3.64 years). The prevalence of ANA positivity was significantly higher among women with PCOS (18.4% vs. 2.29%; p < .001). Though significant correlation was observed between ANA positivity and clinical signs of hyperandrogenism and plasma glucose, no significant correlation was noted between ANA status and other hormonal parameters. Higher prevalence of ANA positivity among women with PCOS, being a marker of autoimmunity, suggests a possible role of autoimmunity in causation of PCOS and needs further elucidation.

Sex hormone binding globulin - an important biomarker for predicting PCOS risk: A systematic review and meta-analysis

Sex hormone-binding globulin (SHBG) is a glycoprotein which regulates bioavailability of sex steroid hormones. Interest in SHBG has escalated in recent years because of its inverse association with polycystic ovary syndrome (PCOS), obesity, insulin resistance, metabolic syndrome, and diabetes type II. This meta-analysis was performed to examine the associations of SHBG with PCOS and to correlate serum SHBG levels with various PCOS associated endocrine and metabolic dysregulation as well as to determine the effects of various therapeutic agents on serum SHBG levels in PCOS patients in order to assess the true accuracy of SHBG in the prediction of PCOS. A literature search was performed using Pub-Med, Science direct, google scholar, EMBASE, and Cochrane library. A total of 675 relevant records were identified, of which 62 articles were included. Meta-analysis using a random-effects model was performed using STATA version 13 to calculate standardized mean difference (SMD) with 95% confidence intervals (95 % CIs). SHBG levels in controls were significantly higher than that of PCOS patients (SMD= -0.83, 95%CI = -1.01, -0.64), with significant heterogeneity across studies (I²= 93.9% and p=0.000). Our results suggest that the lower serum SHBG levels are associated with the risk of PCOS. SHBG may also play an important role in various metabolic disturbances in PCOS patients. Therapeutic interventions improved SHBG levels in PCOS women which further reduced PCOS associated complications. Therefore, SHBG levels may prove to be a useful biomarker for the diagnosis and treatment of PCOS. Systematic review registration: PROSPERO CRD42017057972 Abbreviations: PCOS: polycystic ovary syndrome; SHBG: sex hormone-binding globulin.

Involvement of bone morphogenetic protein activity in somatostatin actions on ovarian steroidogenesis

Somatostatin is expressed in the hypothalamus, pancreas and gastrointestinal tracts and it inhibits the secretion of various hormones in vivo. In the rodent ovary, somatostatin receptor (SSTR) subtypes 2 and 5 are expressed in granulosa cells and oocytes. Somatostatin analogs have been clinically used for treatment of endocrine tumors. For this purpose, relatively high-dose or long-term treatments of somatostatin analogs are necessary; however, the direct and continuous impact of somatostatin analogs on gonadal functions has yet to be elucidated. In the present study, we investigated the effects of somatostatin analogs (octreotide and pasireotide) on ovarian steroidogenesis by rat primary granulosa cell culture. The expression levels of SSTR2 and SSTR5 in granulosa cells were upregulated by FSH treatment. Treatment with somatostatin analogs decreased FSH-induced estradiol production with reduction in aromatase mRNA expression, while the treatment also suppressed FSH-induced progesterone production with reduction of mRNAs levels of StAR, P450scc and 3βHSD2 in granulosa cells. This trend was also observed in a granulosa/oocyte co-culture condition. The effect of pasireotide was more potent than that of octreotide. FSH-induced synthesis of steroids and cAMP was also suppressed by somatostatin analog treatment. Notably, pretreatment with a BMP-binding protein, noggin reversed the suppressive effects of somatostatin analogs on progesterone and cAMP production, suggesting that the endogenous BMP system is functionally involved in the SSTR effects in granulosa cells. Treatment with BMP-2, -4, -6 and -7 decreased the mRNA expression of inhibitory Smads6 and 7, leading to enhancement of BMP actions detected by Id-1 transcription in granulosa cells. Collectively, the results revealed that SSTR activation modulates ovarian steroidogenesis by upregulating endogenous BMP activity in growing follicles.

Use of insulin-sensitizing agents in the treatment of polycystic ovary syndrome

The role of insulin sensitizing agents is discussed at length in this Committee Opinion.

Metformin and polycystic ovary syndrome

PURPOSE OF REVIEW

The aim of this article is to describe the role of insulin resistance in the etiology of polycystic ovary syndrome and to review the results of treatment with the insulin sensitizing drug metformin.

RECENT FINDINGS

Polycystic ovary syndrome is a heterogeneous combination of clinical, hormonal, and reproductive abnormalities associated with insulin resistance and increased cardiovascular risk factors. Reduction of hyperinsulinism and improvement of insulin sensitivity with metformin has been reported to ameliorate these abnormalities in many, but not all studies, with few adverse effects.

SUMMARY

Metformin may be the drug of first choice for most, if not all women with polycystic ovarian syndrome, either alone or in combination with other treatments. Further investigation is necessary to determine the optimal dose and duration of treatment necessary to maximize response.

Dermatologic manifestations of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) affects 5-10% of reproductive-aged women and is one of the most common endocrine disorders in women. The disorder is commonly characterized by elevated levels of androgen and insulin. Women with PCOS may present with a range of signs and symptoms, and face increased risks of reproductive, metabolic, cardiovascular, psychologic, and neoplastic sequelae, particularly if the condition is left unrecognized or untreated. The clinical definition of PCOS has changed in recent years and includes as one of its cardinal criteria the dermatologic manifestations of hyperandrogenism, chiefly hirsutism, acne vulgaris, and androgenetic alopecia. Acanthosis nigricans, a cutaneous sign of hyperinsulinemia, may also be present. These dermatologic features may provide early clinical clues to recognition of PCOS, and treatment of these cutaneous conditions may improve the patient's quality of life and psychologic well-being. The effects of androgen on pilosebaceous units in the skin can vary by anatomic location, producing pathophysiologic effects on hair growth and differentiation, sebaceous gland size and activity, and follicular keratinization. Treatment modalities may include hormonal therapy intended to modulate androgen production and action as well as non-hormonal therapies directed toward specific dermatologic conditions.

Obesity and the role of gut and adipose hormones in female reproduction

Reproductive function declines at both extremes of human energy balance. The relationship between obesity and reproductive function is complex and incompletely understood. The literature has established the negative impact of excess energy stores on ovulatory function and investigated the mechanisms whereby this occurs. Furthermore, weight loss in obese anovulatory women increases ovulation and conception. Obesity and anti-obesity therapy effects on the endometrium, implantation and early fetal development have received less attention. The discovery of adipokines and enterokines greatly expands the ability to investigate the relationship between obesity, therapies to produce weight loss and reproductive function. In this review, we discuss select adipose and enteric signals. We focus on in vitro, animal and human data that lend biological plausibility to adipokines and enterokines as mediators of obesity and reproduction. Very little published work exists that directly addresses adipocyte and enteric signals in this specific role; therefore, much of this review is on the basis of a synthesis of the literature in three areas: (i) in vitro and in vivo evidence regarding the reproductive effects of these signals; (ii) adipokine and enterokine changes that occur with weight-loss therapies, focusing on hypocaloric diets, bariatric surgery and drugs that target adipocyte or enteric signals and (iii) reproductive changes produced by these weight-loss therapies.

Hyperglycaemia acutely decreases circulating dehydroepiandrosterone levels in healthy men

OBJECTIVE

This study was conducted in order to evaluate the effect of glucose-insulin homeostasis on adrenal steroids and was designed to separate the effects of hyperglycaemia from those of insulin.

DESIGN

Eight healthy men aged 22.6 +/- 3.4 (SD) underwent an 80 mU/m2/min hyperinsulinaemic euglycaemic 100-min clamp, a 200-min graded glucose infusion at 2-16 mg/kg/min and a measurement of fat mass.

MEASUREMENTS

Circulating glucose, insulin and adrenal steroid levels including dehydroepiandrosterone (DHEA) were determined before and during both infusion tests. Steroid variations in relation to insulinaemia and glycaemia were analysed using univariate, multivariate tests and nonlinear mixed models.

RESULTS

Hyperinsulinaemia induced no significant modification of adrenal steroid levels. By contrast, hyperglycaemia decreased all adrenal steroids except DHEA-sulphate by 47-66%. The drop occurred early, averaging 51% for 17OH pregnenolone and 57% for DHEA at the 80th minute of glucose infusion, whereas blood glucose was 7.1 +/- 1.2 mmol/1. This effect was independent of insulinaemia, fat mass and waist circumference. Thus, we estimated models that could best predict steroid variations according to blood glucose. At thresholds defining impaired fasting glycaemia and diabetes, the estimated decrease in DHEA was 40% and 45%, respectively, culminating at 60% at 9.3 mmol/1 glycaemia, with no detectable further decrease.

CONCLUSIONS

Our data suggest that hyperglycaemia dramatically decreases adrenal androgen levels in men, possibly by acting at early steps of synthesis, independently of insulinaemia and fat mass.

Efficacy of octreotide-LAR in dieting women with abdominal obesity and polycystic ovary syndrome

CONTEXT

Somatostatin reduces LH, GH, and insulin, and somatostatin receptors are present at the ovarian level; somatostatin analogs are thus potential candidates for treatment of the polycystic ovary syndrome (PCOS).

OBJECTIVE

The purpose of this study was to evaluate the effect of octreotide-LAR, a long-acting somatostatin analog, in anovulatory abdominal obese women with PCOS.

DESIGN

A single-blind, placebo-controlled study was performed, lasting for 7 months.

SETTING

The patients were ambulatory throughout the study.

PATIENTS

Twenty PCOS subjects were enrolled. Eighteen completed the study.

INTERVENTIONS

A low-calorie diet was given during the first month, a low-calorie diet plus octreotide-LAR (10 mg; n = 10 subjects) or placebo (n = 10 subjects) was then given, with one im injection every 28 d (for 6 months).

MAIN OUTCOME MEASURES

The main outcome measures were clinical features, computerized tomography measurement of fat distribution, androgens, GH, IGF-I, IGF-binding proteins (IGFBPs), fasting and glucose-stimulated insulin, and ovulation.

RESULTS

Octreotide had no additional effect in reducing body fat or improving fat distribution than placebo. Conversely, octreotide produced an additional decrease in fasting (P = 0.018) and glucose-stimulated (P = 0.038) insulin levels, an increase in IGFBP-2 (P = 0.042) and IGFBP-3 (P = 0.047), and an improvement in hirsutism (P = 0.004). Moreover, a trend toward greater reductions in testosterone (P = 0.061) and androstenedione (P = 0.069) was observed in women treated with octreotide-LAR compared with those given placebo. All women treated with octreotide ovulated at the end of the study compared with only one of those receiving placebo (P < 0.001).

CONCLUSIONS

Octreotide-LAR may be usefully applied to hypocalorically dieting, abdominal obese PCOS women to improve hyperandrogenism and the insulin-IGF-I system. Restoration of ovulatory menstrual cycles appears to be another advantage of this treatment.

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.

The therapeutic potential of somatostatin receptor ligands in the treatment of obesity and diabetes

Since the development of synthetic somatostatin analogues, several therapeutic applications for somatostatin receptor agonist molecules have been defined. Established applications for somatostatin analogue treatment include pituitary tumours (growth hormone and thyrotropin-secreting adenomas), neuroendocrine tumours of the pancreas and gastrointestinal tract (so-called carcinoid tumours, vasoactive intestinal tumours) and gastroenterological conditions (pancreatitis, gastrointestinal bleedings, refractory diarrhoeas, pancreatic and intestinal fistulas, diarrhoea in AIDS). Further areas for development of somatostatin analogue therapy include obesity, polycystic ovary syndrome and diabetes mellitus, dysmetabolic conditions that are often interrelated. The challenge for the future will be to transform results from clinical trials conducted in heterogeneous clinical situations into novel options of somatostatin analogue use. Since obesity and diabetes mellitus both are disorders of marked heterogeneity, the subgroup of patients that will benefit most from somatostatin analogue treatment has yet to be defined. In addition, the development of more universal ligands covering all of the known somatostatin receptor molecules as well as receptor subtype specific agents is currently underway. The establishment of slow-release depot formulations of octreotide and lanreotide has already provided a more acceptable and consistent delivery mechanism. Use of biodegradable polymer microsphere formulations provides the basis for the development of novel applications, which include hyperinsulinaemia, obesity and polycystic ovary syndrome as components of the dysmetabolic syndrome. The most developed thus far is the use of octreotide in hyperinsulinaemic forms of obesity and in distinct stages of diabetic retinopathy.

Troglitazone, an insulin-sensitizing thiazolidinedione, represses combined stimulation by LH and insulin of de novo androgen biosynthesis by thecal cells in vitro

Polycystic ovarian syndrome (anovulatory hyperandrogenism) is marked by adolescent onset of systemic hyperinsulinism, oligoovulation, hirsutism, excessive LH and androgen secretion, and variable reduction in fertility. Insulin and LH are believed to act in concert to promote ovarian androgen hypersecretion in this disorder. Administration of troglitazone, an insulin-sensitizing agent and putative PPAR gamma agonist, can decrease hyperinsulinism, suppress T production, and ameliorate oligoovulation in some women with this endocrinopathy. The present study tests the hypothesis that troglitazone directly inhibits de novo androgen biosynthesis stimulated jointly by LH and insulin in primary cultures of (porcine) thecal cells. We show that troglitazone dose-dependently antagonizes LH/insulin's combined stimulation of androstenedione and T production by thecal cells in vitro. Consistent steroidogenic inhibition of 80-95% was achieved at drug concentrations of 3-6.8 microM (P < 0.001). Exposure of thecal cells to the thiazolidinedione derivative also blocked bihormonally stimulated accumulation of CYP17 (cytochrome P450 17 alpha-hydroxylase/C(17-20) lyase) gene expression, as reflected by decreased accumulation of cognate heterogeneous nuclear RNA and mRNA (by 30-65%; P < 0.05). Moreover, troglitazone suppressed LH/insulin-induced phosphorylation of the 52-kDa immunoprecipitated CYP17 enzyme by 88% (P < 0.001). A putative natural agonist of PPAR gamma nuclear transcription, 15-deoxy-delta-12,14-prostaglandin J(2), also inhibited LH/insulin-driven androstenedione biosynthesis and CYP17 gene expression in thecal cells. In conclusion, a synthetic thiazolidinedione (troglitazone) and a natural ligand of PPAR gamma (15-deoxy-delta-12,14-prostaglandin J(2)) effectively impede the concerted stimulation by LH and insulin of in vitro thecal cell androgen production, CYP17 gene expression, and CYP17 protein phosphorylation. This ensemble of inhibitory actions on LH/insulin-stimulated steroidogenesis offers a plausible mechanistic basis for at least part of the observed clinical efficacy of troglitazone in mitigating androgen excess in women with polycystic ovarian syndrome.

Clinical, endocrine and metabolic effects of acarbose, an alpha-glucosidase inhibitor, in PCOS patients with increased insulin response and normal glucose tolerance

BACKGROUND

The aim of this study was to evaluate whether treatment with acarbose, an alpha-glucosidase inhibitor, improved hyperandrogenic symptoms, insulin and androgen serum concentrations in hyperinsulinaemic patients with polycystic ovary syndrome (PCOS).

METHODS

30 hyperinsulinaemic women with PCOS and 15 controls were evaluated. Patients were randomized, using a computer-generated randomization list, into two groups of 15 each and treated with placebo or 300 mg/day of acarbose for three months. Hirsutism and acne/seborrhoea scores, hormonal and sex hormone binding globulin serum concentrations, glycaemia and insulin responses to a standard oral glucose load (75g) were measured in all patients before and after three months of treatment.

RESULTS

A significant reduction of the acne/seborrhoea score was observed in patients treated with acarbose and eight of them resumed a regular menstrual rhythm. These clinical improvements were associated with a significant reduction of the insulin response to glucose load, a significant decrease of LH, total testosterone and androstenedione and with a significant increase of sex hormone binding globulin serum concentrations. The serum concentrations of FSH, dehydroepiandrosterone sulphate, prolactin and 17alpha-hydroxyprogesterone did not change significantly. No clinical, metabolic and hormonal modifications were observed in PCOS patients treated with placebo.

CONCLUSIONS

This is the first report showing a reduction of the acne/seborrhoea score in hyperinsulinaemic patients with PCOS treated with acarbose. This improvement was associated with a significant decrease of the insulin response to oral glucose load and of LH and androgen serum concentrations and with a significant rise of sex hormone binding globulin concentration.

Sensitization to insulin in adolescent girls to normalize hirsutism, hyperandrogenism, oligomenorrhea, dyslipidemia, and hyperinsulinism after precocious pubarche

Precocious pubarche in girls is often preceded by low weight at birth and followed by hirsutism, ovarian hyperandrogenism, and oligomenorrhea in adolescence, the latter usually being accompanied by dyslipidemia and hyperinsulinism, which are, in turn, two major risk factors for cardiovascular disease in later life. We hypothesized that insulin resistance may be a key pathogenetic factor in this sequence. We tested the hypothesis by assessing the effects of an insulin-sensitizing agent, metformin, given at a daily dose of 1275 mg for 6 months to 10 nonobese adolescent girls (mean age, 16.8 yr; body mass index, 21.9 kg/m2; birth weight, 2.7 kg) with hirsutism, ovarian hyperandrogenism (diagnosis by GnRH agonist test), oligomenorrhea, dyslipidemia, and hyperinsulinemia after precocious pubarche. Before the metformin trial, longitudinal studies in these girls had shown that hyperinsulinism was present at prepubertal diagnosis of precocious pubarche, and that it increased markedly in late puberty or early postmenarche. Metformin treatment was well tolerated and was accompanied by a marked drop in hirsutism score, insulin response to oral glucose tolerance test, free androgen index, and baseline testosterone, androstenedione, dehydroepiandrosterone, and dehydroepiandrosterone sulfate levels (all P < 0.01). During metformin treatment, the LH and 17-hydroxyprogesterone hyperresponses to GnRH agonist were attenuated (P < 0.01); serum triglyceride, total cholesterol, and low density lipoprotein cholesterol levels decreased; and high density lipoprotein cholesterol rose. All girls reported regular menses within 4 months. Withdrawal of metformin treatment was followed, within 3 months, by a consistent reversal toward pretreatment conditions. In conclusion, metformin treatment reduced hyperinsulinemia, hirsutism, and hyperandrogenism; attenuated the LH and 17-hydroxyprogesterone hyperresponses to GnRH agonist; improved the atherogenic lipid profile; and restored eumenorrhea in nonobese adolescent girls with a history of precocious pubarche. These observations corroborate the idea that insulin resistance may indeed be a prime factor underpinning the sequence from reduced fetal growth, through precocious pubarche, to adolescent endocrinopathies that are reminiscent of so-called polycystic ovary syndrome.