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Context: Despite the very high prevalence of the polycystic ovary syndrome (PCOS), the underlying pathogenetic mechanism has remained obscure., Objective: To determine the cause of two sisters' PCOS associated with severe insulin resistance., Design: Clinical case report. Methods Two sisters who presented with hyperandrogenism and menstrual disorders in the context of PCOS, and were subsequently found to be severely insulin resistant. Physical examination revealed muscular hypertrophy with a paucity of fat in the extremities, trunk and gluteal regions, in spite of excess fat deposits in the face, neck and dorsocervical region. Known genes involved in familial partial lipodystrophy were screened. At the same time, metformin (1700 mg/day) was commenced. After 2-3 years of uninterrupted therapy, lack of clinical improvement led to the introduction of pioglitazone (30 mg/day)., Results: Both sisters were found to be heterozygous for the R482Q mutation in the lamin A/C gene (LMNA) gene, establishing the definitive diagnosis as Dunnigan-type familial partial lipodystrophy complicated by severe insulin resistance and secondary PCOS. Treatment with pioglitazone resulted in progressive amelioration of insulin resistance, hyperinsulinaemia and hyperandrogenaemia. Menses also improved, with restoration of a eumenorrhoeic pattern, and the framework of ultrasound PCO was in complete remission., Conclusions: Assessment of insulin sensitivity and adipose tissue topography should be a key part of the initial evaluation of patients with PCOS. Identifying such forms of PCOS with monogenic insulin resistance as the primary pathogenic abnormality may have practical implications for therapy, since they respond to thiazolidinediones, but not to metformin.

Objective: We measured blood levels of obestatin, total ghrelin, and the ghrelin/obestatin ratio and their relationship with anthropometric and metabolic parameters, adiponectin and insulin resistance, in overweight/obese and normal-weight women., Design: Outpatients Unit of Endocrinology of the S Orsola-Malpighi Hospital of Bologna, Italy., Methods: Fasting obestatin, ghrelin, adiponectin and lipid levels, fasting and glucose-stimulated oral glucose tolerance test insulin, and glucose levels were measured in 20 overweight/obese and 12 controls. The fasting ghrelin/obestatin ratio was calculated; the homeostasis model assessment-IR (HOMA-IR) and insulin sensitivity index (ISI(composite)) were calculated as indices of insulin resistance., Results: Obese women had higher obestatin and lower ghrelin blood levels, and a lower ghrelin/obestatin ratio compared with controls. In all subjects, obestatin was significantly and positively correlated with total cholesterol and triglycerides, but not with ghrelin, anthropometric, and metabolic parameters. In the obese women, however, obestatin and ghrelin concentrations were positively correlated. By contrast, the ghrelin/obestatin ratio was significantly and negatively correlated with body mass index, waist, waist-to-hip ratio, fasting insulin, and HOMA-IR, and positively with ISI(composite) but not with adiponectin. None of these parameters were correlated with the ghrelin/obestatin ratio in the obese., Conclusions: Increased obestatin, decreased ghrelin levels, and a decreased ghrelin/obestatin ratio characterize obesity in women. This supports the hypothesis that the imbalance of ghrelin and obestatin may have a role in the pathophysiology of obesity. On the other hand, some relevant differences between our data on circulating levels of obestatin and the ghrelin/obestatin ratio in obese subjects and those reported in the few studies published so far imply that further research is needed.

Context: Elevated adrenal androgen levels are common in polycystic ovary syndrome (PCOS), but the underlying pathogenetic mechanism is poorly understood. In the rare cortisone reductase deficiency, impaired regeneration of active cortisol from inert cortisone by 11beta-hydroxysteroid dehydrogenase (11beta-HSD1) results in compensatory activation of ACTH secretion and adrenal hyperandrogenism. 11beta-HSD1 deficiency may protect against obesity and its metabolic consequences because of impaired regeneration of cortisol in adipose tissue., Objective: Our objective was to investigate a functional polymorphism in HSD11B1 (T-->G in the third intron rs12086634, which associates with lower 11beta-HSD1 activity) in PCOS with and without obesity., Design and Setting: We conducted a case-control study in lean and obese PCOS patients and controls at an academic hospital., Participants: Participants included 102 Caucasian PCOS patients and 98 controls comparable for age, weight, and race., Main Outcome Measures: We assessed genotype distribution and influence of genotypes on clinical, hormonal, and metabolic parameters., Results: The G allele was significantly related to PCOS status (P = 0.041), and this association was mainly attributable to lean (P = 0.025), rather than obese (P = 0.424), PCOS patients. The G allele was associated with lower 0800-0830 h plasma cortisol (P < 0.001) and higher cortisol response to ACTH(1-24) (P < 0.001) in all women with PCOS and with higher dehydroepiandrosterone sulfate levels (P < 0.001), greater suppression of dehydroepiandrosterone sulfate by dexamethasone (P < 0.001), and lower fasting plasma low-density lipoprotein cholesterol (P = 0.002) levels in lean PCOS women., Conclusions: Genetic variation in 11beta-HSD1 contributes to enhanced cortisol clearance and compensatory adrenal hyperandrogenism in lean patients with PCOS but may be protective against obesity and some features of the metabolic syndrome.

Objective: This study was carried out to investigate the role of sex in the regulation of the hypothalamic-pituitary-adrenal (HPA) axis and its relationship with testosterone levels in male and female obesity., Research Methods and Procedures: Twenty-two obese men (OB-M) and 29 obese women (OB-W) participated in the study. Two groups of normal weight men (NW-M) and women (NW-W), respectively, served as controls. In basal conditions, blood concentrations of major androgens, sex hormone-binding protein, and gonadotropins were assessed, and the free androgen index (testosterone x100/sex hormone-binding globulin) was calculated. All subjects underwent a combined corticotropin-releasing hormone plus arginine-vasopressin stimulation test., Results: OB-M and NW-M had higher basal adrenal cortical tropic hormone (ACTH) and cortisol levels than their female counterparts. In addition, ACTH, but not cortisol basal, levels were significantly higher in obese than in normal weight controls in both sexes. OB-W had a higher response than OB-M to the combined corticotropin-releasing hormone plus arginine-vasopressin test of both ACTH and cortisol [expressed as incremental percentage of area under the curve (AUC%)]. The same finding was present between NW-W and NW-M. Basal luteinizing hormone levels were negatively correlated to ACTH(AUC%) in both OB-W and OB-M. In the OB-W, however, a positive correlation was found between cortisol(AUC%) and testosterone (r = 0.48; p = 0.002), whereas a tendency toward a negative correlation was present in OB-M., Discussion: In conclusion, we have shown a significant positive relationship between the activity of the HPA axis and testosterone in obese women, which suggests a partial responsibility of increased HPA axis activity in determining testosterone levels. In addition, it clearly seems that, as reported in normal weight subjects, a sex difference in the HPA axis activity still persists even in the presence of obesity.

Objective: Arginine vasopressin (AVP) has a central role in the response of the hypothalamic-pituitary-adrenal (HPA) axis to stress conditions. A low dose of AVP has been shown to have a modest, but significant effect on ACTH response in normal weight subjects. The aim of this study was to test the response of the HPA axis in obese subjects in order to assess eventual primary neuroendocrine alterations, previously demonstrated by using AVP combined with corticotropin releasing hormone (CRH). In addition, given its central inhibitory action on the HPA axis, we investigated whether the suppressive capacity of alprazolam (APZ) pretreatment on the hormone response to low-dose AVP challenge and daily urinary free cortisol (UFC) excretion rate may be altered in the presence of obesity., Design: Fifteen overweight or obese women and eight normal-weight controls randomly underwent two low-dose AVP tests (0.3 UI iv bolus), one without (AVP test) and the other preceded by APZ administration (0.5 mg at midnight and 0.5 mg 90 min before the test in the morning at 08:30 h) (APZ/AVP test). Blood samples for ACTH and cortisol assay were obtained at baseline and throughout each test. The day before each test, 24h-UFC/ creatinine was also mea-sured., Results: Basal ACTH levels were similar in the two groups, whereas cortisol concentrations were significantly lower in the overweight/obese group. Overweight/obese women had higher ACTH and cortisol responses to the AVP tests and significantly greater hormone inhibition after APZ than controls. In both groups, AVP-induced delta-peak cortisol values before and after APZ pre-treatment were significantly correlated. Body fat distribution had no effect on the HPA axis response to AVP either before or after APZ. Moreover, APZ decreased 24h-UFC/creatinine values unsignificantly in controls and by approximately 50% in the overweight/obese subjects. These changes were unrelated to the cortisol response to the AVP test before and after APZ pretreatment. On the other hand, percent changes of 24h-UFC/creatinine after APZ were negatively related to the body mass index (BMI) but positively with waist circumference values, which indicates that the abdominal obesity phenotype may counteract the 24 h-UFC/creatinine that would be expected on the basis of BMI values., Conclusions: Our data further support the concept that in women obesity may represent a condition of hyperresponsiveness or hypersensitivity of the HPA axis to neuroendocrine stimuli, which appear to be independent of feedback control. In addition, the data on the inhibiting capacity of APZ on UFC excretion confirm that the alterations of the HPA axis in obesity is particularly evident in the abdominal phenotype.

Background: Hyperandrogenism, hyperinsulinaemia and obesity play a key and coordinating roles in the pathogenesis of polycystic ovary syndrome (PCOS), contributing in different ways to the clinical expression of the syndrome. Weight loss is beneficial, but the additional administration of insulin-lowering drugs, such as metformin, and antiandrogens may produce further benefits, due to their different spectrum of action. The effects of long-term metformin and flutamide, an antiandrogen drug, added alone or in combination with a low-calorie diet, on body weight and fat distribution, androgens, metabolic parameters and clinical status in obese women with PCOS were investigated., Methods: Forty obese women with PCOS were enrolled in the study. After a 1-month diet, according to single-blind design, the patients were allocated to treatment with placebo, metformin (850 mg/orally, twice daily), flutamide (250 mg/orally, twice daily) or metformin (850 mg/orally, twice daily) + flutamide (250 mg/orally, twice daily) for the following 6 months, while continuing hypocaloric dieting. At baseline and at the end of the study, sex hormone, SHBG, lipid, insulin and insulin sensitivity determinations were evaluated. At the same time, clinical parameters such as anthropometry, total (TAT), visceral (VAT) and subcutaneous (SAT) adipose tissue, hirsutism and menses were also measured., Results: We found that, in obese PCOS women, following a hypocaloric diet the addition of metformin, flutamide or the combined metformin + flutamide treatment had some specific additional favourable effects with respect to the low-calorie diet alone. In particular, flutamide treatment seemed to add a significant effect in decreasing visceral fat, androstenedione, DHEA-S, total and low density lipoprotein (LDL) cholesterol and in improving hirsutism. Conversely, metformin had significant benefits on the menstrual status. The two drugs showed an additive effect in reducing testosterone concentrations and a synergistic effect in increasing high density lipoprotein (HDL) cholesterol and SHBG levels. Improvement of insulin sensitivity and hyperinsulinaemia appeared to depend on hypocaloric diet, without any further significant effect of the pharmacological treatments, either alone or in combination., Conclusions: We conclude that, in obese PCOS women, following a hypocaloric diet the addition of metformin, flutamide or the combined metformin + flutamide treatment appears to have a more favourable outcome on body fat distribution, androgens, lipids, hirsutism and menses. However, our data emphasize the dominant role of hypocaloric dieting in improving insulin resistance and hyperinsulinaemia. Therefore, this study provides a rationale for specifically targeting different therapeutical options for PCOS according to the required outcomes.

We recently described a connection between androgens and ghrelin in women affected by the polycystic ovary syndrome. To further investigate the interaction between sex steroids and ghrelin, we investigated circulating ghrelin levels in a group of hypogonadal men before and after therapeutic intervention aiming at normalization low testosterone (T) concentrations. Seven hypogonadal men were compared with nine overweight/moderately obese men matched for body mass index and body fat distribution parameters, as well as with 10 normal weight controls. Total and free T and plasma ghrelin levels were significantly lower in the hypogonadal men than in the control groups. Hypogonadal men also had a significantly higher insulin resistance state. Ghrelin levels were positively correlated with both total and free T concentrations. A significant correlation was also found between ghrelin and the anthropometric parameters and the insulin resistance indexes. However, in a multiple regression analysis in which a correction for all covariants was performed, only the relationship with total and free T persisted. After the 6-month replacement T therapy, ghrelin levels of hypogonadal patients increased and did not differ significantly in comparison with both control groups. The positive correlation between ghrelin and androgens still persisted after T replacement therapy, after adjusting for confounding variables. These data further indicate that sex hormones modulate circulating ghrelin concentrations in humans. This may be consistent with the concept that ghrelin may exert a relevant role in the endocrine network connecting the control of the reproductive system with the regulation of energy balance.

Obesity, particularly the abdominal phenotype, is associated with several reproductive disturbances. Whereas mechanisms by which obesity affect fertility are complex and still not completely understood, an important role appears to be played by the presence of a condition of functional hyperandrogenism and hyperinsulinaemia, which accompanies the insulin-resistant state. In women with the polycystic ovary syndrome, abdominal obesity may be co-responsible for the development of hyperandrogenism and associated chronic anovulation, through mechanisms primarily involving the insulin-mediated overstimulation of ovarian steroidogenesis and decreased sex hormone-binding globulin blood concentrations. By these mechanisms, obesity may also favour resistance to clomiphene and gonadotrophin-induced ovulation and reduce outcomes of IVF/ICSI procedures. Due to the beneficial effects of weight loss, lifestyle intervention programmes should represent the first-line approach in the treatment of infertile obese women. Insulin-sensitizing agents may add further benefits, particularly if administered in combination with hypocaloric dieting. Therefore, individualized pharmacological support aimed at favouring weight loss and improving insulin resistance should be widely extended in clinical practice in obese infertile patients. This may be beneficial even during pregnancy, thereby permitting favourable physiological delivery and healthy babies.