Metabolic Aspects Of Polycystic Ovary Syndrome Research Articles

Pathophysiologic Mechanisms of Insulin Secretion and Signaling-Related Genes in Etiology of Polycystic Ovary Syndrome.

Polycystic ovary syndrome (PCOS) is a common endocrinopathy in women. PCOS is characterized by anovulation, hyperandrogenism, polycystic ovaries, insulin resistance, and obesity. Despite the finding that the genetic origin of PCOS is well demonstrated in previous twin and familial clustering studies, genes and factors that can exactly explain the PCOS pathophysiology are not known. Objective(s). In this review, we attempted to identify genes related to secretion and signaling of insulin aspects of PCOS and their physiological functions in order to explain the pathways that are regulated by these genes which can be a prominent function in PCOS predisposition. Materials and Methods. For this purpose, published articles and reviews dealing with genetic evaluation of PCOS in women from peer-reviewed journals in PubMed and Google Scholar databases were included in this review. Results. The genomic investigations in women of different populations identified many candidate genes and loci that are associated with PCOS. The most important of them are INSR, IRS1-2, MTNR1A, MTNR1B, THADA, PPAR-γ2, ADIPOQ, and CAPN10. These are mainly associated with metabolic aspects of PCOS. Conclusions. In this review, we proposed that each of these genes may interrupt specific physiological pathways by affecting them and contribute to PCOS initiation. It is clear that the role of genes involved in insulin secretion and signaling is more critical than other pathways.

Comparison of two insulin sensitizers, metformin and myo-inositol, in women with polycystic ovary syndrome (PCOS)

Insulin resistance (IR) plays a pivotal role in PCOS. Insulin-sensitizer agents such as metformin and inositols have been shown to improve the endocrine and metabolic aspects of PCOS. The purpose of this study is to compare their effects on the clinical and metabolic features of the women with PCOS. Fifty PCOS women with IR and/or hyperinsulinemia were randomized to treatment with metformin (1500 mg/day) or myo-inositol (4 g/day). IR was defined as HOMA-IR >2.5, while hyperinsulinemia was defined as a value of AUC for insulin after a glucose load over the cutoff of our laboratory obtained in normal women. The Matsusa Index has been calculated. The women have been evaluated for insulin secretion, BMI, menstrual cycle length, acne and hirsutism, at baseline and after 6 months of therapy. The results obtained in both groups were similar. The insulin sensitivity improved in both treatment groups. The BMI significantly decreased and the menstrual cycle was normalized in about 50% of the women. No significant changes in acne and hirsutism were observed. The two insulin-sensitizers, metformin and myo-inositol, show to be useful in PCOS women in lowering BMI and ameliorating insulin sensitivity, and improving menstrual cycle without significant differences between the two treatments.

Genetic, hormonal and metabolic aspects of PCOS: an update.

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder affecting 5–10 % of women of reproductive age. It generally manifests with oligo/anovulatory cycles, hirsutism and polycystic ovaries, together with a considerable prevalence of insulin resistance. Although the aetiology of the syndrome is not completely understood yet, PCOS is considered a multifactorial disorder with various genetic, endocrine and environmental abnormalities. Moreover, PCOS patients have a higher risk of metabolic and cardiovascular diseases and their related morbidity, if compared to the general population.

The polycystic ovary syndrome: a position statement from the European Society of Endocrinology.

Polycystic ovary syndrome (PCOS) is the most common ovarian disorder associated with androgen excess in women, which justifies the growing interest of endocrinologists. Great efforts have been made in the last 2 decades to define the syndrome. The presence of three different definitions for the diagnosis of PCOS reflects the phenotypic heterogeneity of the syndrome. Major criteria are required for the diagnosis, which in turn identifies different phenotypes according to the combination of different criteria. In addition, the relevant impact of metabolic issues, specifically insulin resistance and obesity, on the pathogenesis of PCOS, and the susceptibility to develop earlier than expected glucose intolerance states, including type 2 diabetes, has supported the notion that these aspects should be considered when defining the PCOS phenotype and planning potential therapeutic strategies in an affected subject. This paper offers a critical endocrine and European perspective on the debate on the definition of PCOS and summarises all major aspects related to aetiological factors, including early life events, potentially involved in the development of the disorder. Diagnostic tools of PCOS are also discussed, with emphasis on the laboratory evaluation of androgens and other potential biomarkers of ovarian and metabolic dysfunctions. We have also paid specific attention to the role of obesity, sleep disorders and neuropsychological aspects of PCOS and on the relevant pathogenetic aspects of cardiovascular risk factors. In addition, we have discussed how to target treatment choices based according to the phenotype and individual patient's needs. Finally, we have suggested potential areas of translational and clinical research for the future with specific emphasis on hormonal and metabolic aspects of PCOS.

Comparison of Single and Combined Treatment with Exenatide and Metformin on Menstrual Cyclicity in Overweight Women with Polycystic Ovary Syndrome

Insulin resistance and obesity are common features of the polycystic ovary syndrome (PCOS). Weight loss and use of insulin-lowering drugs have been shown to improve both reproductive and metabolic aspects of PCOS. We evaluated exenatide (EX) and metformin (MET), alone and in combination (COM), on menstrual cyclicity, hormonal parameters, metabolic profiles, and inflammatory markers in overweight, insulin-resistant women with PCOS. Sixty overweight oligoovulatory women with PCOS (body mass index > 27; 18-40 yr) were randomized to one of three treatment groups: MET [1000 mg twice daily (BID)], EX (10 microg BID), or COM (MET 1000 mg BID, EX 10 microg BID) for 24 wk. The primary outcome was menstrual frequency; secondary outcome measures included changes in ovulation rate, insulin action, anthropometric measures, androgen levels, and inflammatory markers. Forty-two (70%) patients completed the study. COM therapy was superior to EX or MET monotherapy in improving menstrual cyclicity, ovulation rate, free androgen index, and insulin sensitivity measures and reducing weight and abdominal fat. Both EX arms were more effective in promoting weight loss than MET (P = 0.003). COM appears better than either EX or MET alone on menstrual cycle frequency and hormonal and metabolic derangements. A marked decrease in central adiposity could partly explain the improvements in reproductive function, insulin-glucose parameters, and adiponectin observed in these overweight women with PCOS treated with COM therapy. Larger trials of longer duration are warranted to assess the long-term efficacy and safety of combined EX-MET therapy in overweight women with PCOS.

Metformin improves polycystic ovary syndrome symptoms irrespective of pre-treatment insulin resistance

Insulin resistance (IR) and obesity are common features of the polycystic ovary syndrome (PCOS). Insulin-sensitizing agents have been shown to improve both reproductive and metabolic aspects of PCOS, but it remains unclear whether it is also beneficial in lean patients without pre-treatment IR. The aim of this study was to determine the influence of metformin on the clinical and biochemical parameters of PCOS irrespective of the presence of basal obesity and IR. The effect of 6 months of metformin treatment was prospectively assessed in 188 PCOS patients, divided into three groups according to body mass index (BMI; lean: BMI<25 kg/m2, overweight: BMI 25-29 kg/m2, and obese: BMI30 kg/m2). Outcome parameters, which were also assessed in 102 healthy controls, included body weight, homeostasis model assessment for IR (HOMA-IR), fasting glucose and insulin levels, area under the curve of insulin response (AUCI), hyperandrogenism, and menstrual irregularities. In comparison with the respective BMI-appropriate control groups, only obese but not lean and overweight PCOS patients showed differences in fasting insulin and HOMA-IR. Metformin therapy significantly improved all outcome parameters except fasting glucose levels. Subgroup analyses revealed that in the group of lean PCOS patients without pre-treatment IR, metformin significantly improved HOMA-IR (1.7+/-1.0 vs 1.1+/-0.7 micromol/lxmmol/l2) and fasting insulin levels (7.7+/-4.2 vs 5.4+/-3.9 mU/l), in addition to testosterone levels (2.6+/-0.9 vs 1.8+/-0.7 nmol/l), anovulation rate (2.3 vs 59.5%), and acne (31.8 vs 11.6%; all P<0.017). In the overweight and obese PCOS groups, metformin also showed the expected beneficial effects. Metformin improves parameters of IR, hyperandrogenemia, anovulation, and acne in PCOS irrespective of pre-treatment IR or obesity.

Benefit of metformin therapy in women with polycystic ovary syndrome is independent of insulin resistance

Introduction: Polycystic Ovary Syndrome (PCOS) is characterised by chronic anovulation paired with infertility and hyperandrogenism. PCOS affects 5–10% of reproductive age women. 50% of PCOS patients are obese. Insulin sensitising agents have been shown to improve both reproductive and metabolic aspects of PCOS. Not all of PCOS affected women are insulin resistant and it is not clear whether insulin resistance is part of the pathogenesis of PCOS.