Insulin resistance and polycystic ovarian syndrome.

Insulin resistance (IR) and polycystic ovarian syndrome (PCOS) appear as linked phenomena, although this is not easy to obviate in common forms of PCOS while it is evident in the rare cases of extreme IR and hyperinsulinism (HI). Experimental data indicate that insulin could interfere with the local insulin-like growth factor systems in ovaries, and presumably in adrenals and in the hypothalamic pituitary system. The female puberty system offers a physiological model to explain the gonadotropic action of insulin. In patients with IR, HI could induce a state of hyperpuberty, leading to the constitution of PCOS during adolescence.     

Ovarian steroidogenesis in Japanese patients with polycystic ovary syndrome

Gonadotropin and steroid hormone levels in both peripheral and ovarian venous blood were measured in samples obtained from 20 Japanese patients with polycystic ovary syndrome (PCOs) and 10 normal women in early follicular phase (normal women) by radioimmunoassay. The change in the amount of steroid hormone following intravenous human menopausal gonadotropin (HMG) or dexamethasone administration was investigated. The mean concentration in patients with PCOs was significantly higher than the concentrations found in normal women for LH (p less than 0.001), but not for FSH in peripheral blood. Significantly elevated ovarian venous steroid hormone levels in PCOs were found for 17 alpha-hydroxypregnenolone (p less than 0.05), progesterone (p less than 0.05), 17 alpha-hydroxyprogesterone (p less than 0.01), 4 delta-androstenedione (p less 0.01), testosterone (p less than 0.01), estrone (p less than 0.01) and estradiol (p less than 0.05), but not for dehydroepiandrosterone-sulfate (DHEAS). The ovarian dehydroepiandrosterone (DHEA) level was slightly elevated in PCOs. The concentration of ovarian 4 delta-androstenedione in PCOs reached twelve times as much as that in normal women. After the administration of HMG, all of the ovarian venus steroid hormone levels were elevated slightly and without significance in the short observation time for 10 min. The DHEAS level was suppressed while the ovarian DHEA level remained high in PCOs following dexamethasone administration. These findings seem to indicate there is no adrenal involvement and no adrenal-like component in the ovary of PCOs, and no evidence of 3 beta-hydroxysteroid dehydrogenase and/or aromatase deficiency in this study. The increase in the steroid hormone secretion in PCOs is explained by the increase in ovarian production in polycystic enlarged ovaries.     

Molecular mechanisms of insulin resistance in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrinopathy of unknown aetiology that affects women of reproductive age. During the past ten years, defective insulin activity in PCOS has been demonstrated in target tissues and causes insulin resistance and hyperinsulinaemia. Furthermore, presence of insulin receptors in the ovarian tissue and overproduction of androgens by theca cells leads to characteristic hyperandrogenaemia. Recent data suggest a divergence in post-receptor signalling pathways for insulin in its target tissues (muscle, adipocytes and ovarian tissue), where the metabolic pathway of insulin activity is defective, whereas the activation of steroidogenesis is maintained. Investigators are still searching for clues to understand the cause of this enigmatic syndrome, despite great advances in molecular medicine and genetics.     

Metabolic syndrome in polycystic ovary syndrome

Both metabolic syndrome (MS) and polycystic ovary syndrome (PCOS) are common among women. The exact prevalence of MS in women with PCOS is dependent upon the diagnostic criteria used for each. However, the frequent co-occurrence of both MS and PCOS in women is suggestive of a common aetiology. In this short review article we argue that insulin resistance, as a consequence of abdominal obesity, may represent such a common aetiology. We also review the literature on the prevalence of MS in women with PCOS and consider the impact that the particular criteria used to diagnose both MS and PCOS may have had on these estimates of prevalence.     

Elevated ghrelin plasma levels in patients with polycystic ovary syndrome.

Polycystic ovary syndrome is a common endocrine disorder in women. It is associated with hirsuitism, obesity, insulin resistance, abnormality in the growth hormone/insulin-like growth factor I (IGF-1) axis and polycystic ovaries. The etiology of PCOS has not been clarified. Ghrelin is an endogenous ligand of the growth hormone secretagogue receptor. It is mainly secreted by stomach cells but has also been shown to be present in hypothalamus, pituitary, pancreas and gonads. Ghrelin is a regulator of energy homeostasis and GH secretion. The influence of ghrelin on insulin secretion and gonadal function is known. Since ghrelin may play an important role in pathophysiology of PCOS, we studied ghrelin levels in a group of 52 women with PCOS and in 16 women in a control group. Plasma levels of insulin, total testosterone, SHBG, LH, and FSH were also measured. In conclusion, PCOS women have higher ghrelin levels than controls. Ghrelin negatively correlates with BMI and insulin levels in PCOS group. A relation between ghrelin and SHBG was observed. Our data suggest that ghrelin could be the possible link in PCOS etiology.     

Hyperinsulinism and insulin resistance in the polycystic ovary syndrome as tested with tolbutamide

The aim of this research was to study both insulin secretion and insulin resistance index (IRI) in seventeen females, aged 16-30, affected by polycystic ovarian syndrome. The diagnosis was made using clinical, hormonal, radiological and echographic criteria. Eight healthy women, carefully matched with our patients for age and for statistical obesity incidence, were studied as controls. Both glycemic and insulinemic curves, areas, insulinemic/glycemic area ratio (IRI) were studied by tolbutamide test (1 g i.v.). Areas were assessed by planimeter, blood glucose by Trinder method, blood insulin by a RIA method, statistical study by t Student test and correlation coefficients. These latter were determined by comparing individual plasma testosterone, FSH, LH and LH/FSH ratio values together with urinary total 17-ketosteroid and delta HEA output values on the one hand and insulin areas and IRI values on the other. Increased glycemic areas, insulinemic peaks and areas, associated with markedly increased IRI values, were observed in the patients. A correlation exists between hyperinsulinism, insulin resistance on the one hand and increased urinary androgens output on the other. delta HEA resulted particularly increased over other androgenic fractions.     

多囊卵巢综合征患者血清VitD水平及与炎症因子之间的相关性研究

目的 了解多囊卵巢综合征（PCOS）患者血清中25-羟维生素D（25-OH-VitD3）水平情况,并探讨其与白细胞介素-6（IL-6）、肿瘤坏死因子（TNF-α）、转化生长因子（TGF-β）、单核细胞趋化蛋白-1（MCP-1）及C-反应蛋白（CRP）之间的相关性。方法 选择2017年8月—2018年12月来医院妇科门诊就诊并确诊为PCOS的患者共135例作为PCOS组,选择同期来医院体检的健康妇女共120例作为对照组,采用化学发光法检测血清中25-OH-VitD3水平,免疫比浊法检测CRP水平及采用酶联免疫吸附法（ELISA）检测IL-6、TNF-α及TGF-β水平,并对检测结果进行统计学分析。结果 PCOS组患者血清中25-OH-VitD3水平为31.87±6.29 nmol/L,明显低于对照组的65.08±13.76 nmol/L,差异有统计学意义（t=3.190,P<0.05）。PCOS组患者血清IL-6、TNF-α、TGF-β、MCP-1及CRP水平分别为23.71±11.23 ng/L、20.54±3.16 ng/L、76.54±8.03 ng/L、375.92±40.15 ng/L及13.48±3.10 mg/L,均明显高于对照组,差异均有统计学意义（t=9.065,8.091,10.178,13.052,7.059,Ps<0.05）。通过Pearson相关性分析,25-OH-VitD3水平与IL-6、TNF-α、TGF-β、MCP-1及CRP水平均呈明显的负相关（r= -0.562,-0.628,-0.780,-0.850,-0.505,Ps<0.05）。结论 25-OH-VitD3低表达水平可能通过其免疫调节及抑制炎症因子生成能力下降,引起各种炎症因子水平升高,导致PCOS的发病。因此,维生素D可能与PCOS病的发生和发展有密切关系。     

Neuroendocrine dysfunction in polycystic ovary syndrome

Polycystic ovarian syndrome (PCOS) is a common disorder characterized by ovulatory dysfunction and hyperandrogenemia (HA). Neuroendocrine abnormalities including increased gonadotropin-releasing hormone (GnRH) pulse frequency, increased luteinizing hormone (LH) pulsatility, and relatively decreased follicle stimulating hormone contribute to its pathogenesis. HA reduces inhibition of GnRH pulse frequency by progesterone, causing rapid LH pulse secretion and increasing ovarian androgen production. The origins of persistently rapid GnRH secretion are unknown but appear to evolve during puberty. Obese girls are at risk for HA and develop increased LH pulse frequency with elevated mean LH by late puberty. However, even early pubertal girls with HA have increased LH pulsatility and enhanced daytime LH pulse secretion, indicating the abnormalities may begin early in puberty. Decreasing sensitivity to progesterone may regulate normal maturation of LH secretion, potentially related to normally increasing levels of testosterone during puberty. This change in sensitivity may become exaggerated in girls with HA. Many girls with HA-especially those with hyperinsulinemia-do not exhibit normal LH pulse sensitivity to progesterone inhibition. Thus, HA may adversely affect LH pulse regulation during pubertal maturation leading to persistent HA and the development of PCOS.     

Proteomics and polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder of heterogeneous etiology. Proteomics techniques have been used for elucidating the physiopathology of PCOS, yet the proteins identified so far were rarely the same across tissues and studies. The present review discusses the current challenges in the application of proteomics to the study of PCOS. A well-defined research design and an appropriate selection of study populations, samples and proteomic platforms are essential in clinical proteomics. Furthermore, the findings derived from proteomic approaches should be validated by complementary techniques, and the reproducibility of the results has ideally to be confirmed by different studies. Only when meeting these requirements, the proteins identified by proteomic techniques should be considered as candidates for future studies aiming to define specific molecular phenotypes of PCOS and their possible role in the metabolic and hormonal abnormalities characteristic of this syndrome.     

Serum metabolomics analysis of patients with polycystic ovary syndrome by mass spectrometry

Polycystic ovary syndrome (PCOS) is a set of symptoms caused by elevated androgens (male hormones) in females. PCOS is the most common endocrine disorder among women between 18 and 44 years. Currently, the pathogenesis of PCOS remains unclear. Liquid chromatography–mass spectrometry (LC/MS)‐based metabolomics is becoming more and more useful for medical research, especially in revealing the mechanism of the disease. The aim of this study was to investigate the difference of serum metabolic profiles in patients with PCOS and healthy control to better understand the mechanism of this disease. Ten patients with PCOS and 10 healthy people were recruited for this study. The serum samples were collected for LC/MS analysis. Multivariate statistical analysis was performed to discover and identify the potential biomarkers. Six biomarkers were found and identified. The biomarkers belonged to different metabolic pathway including lipid metabolism, carnitine metabolism, androgen metabolism, and bile acid metabolism. Those biomarkers also played different roles in disease progression. Metabolomics is a powerful tool used in research of the mechanism involved in this disease to provide useful information for better understanding of PCOS.     

Lipid disturbances in women with polycystic ovary syndrome.

Small but detectable disturbances concerning blood lipid levels manifested by somewhat higher concentrations of LDL-cholesterol and triglycerides as well as higher values of atherogenic indices expressing the ratio of cholesterol present in atherogenic lipoprotein fractions to that present in atheroprotective HDL fraction have been shown to exist in 36 women with polycystic ovary syndrome. HDL-cholesterol concentration was lower in women with polycystic ovary syndrome than in healthy women. The disturbances described above were more pronounced in obese patients. No correlation was found between the disturbances in lipid levels and hormonal disturbances particularly hyperandrogenemia.     

Antiandrogenic contraceptives increase serum adiponectin in obese polycystic ovary syndrome patients

Increasing evidence suggests that adipocyte function is altered in the polycystic ovary syndrome (PCOS) as a result of androgen excess, providing an explanation for its frequent association with abdominal adiposity and insulin resistance. We here compared the response of serum adiponectin and leptin levels to the amelioration of androgen excess by means of treatment with an antiandrogenic oral contraceptive pill, as compared with the response to insulin sensitization with metformin. Thirty-four women presenting with PCOS were randomized to treatment with an oral contraceptive containing 35 microg ethinyl-estradiol plus 2 mg cyproterone acetate (Diane(35) Diario) or with metformin (850 mg twice daily). Serum adiponectin and leptin levels were evaluated at baseline and after 12 and 24 weeks of treatment. In obese PCOS women, treatment with Diane(35) Diario resulted in an increase in serum adiponectin levels and in the adiponectin/leptin ratio, in parallel with a marked decrease in serum androgen concentrations, whereas no statistically significant changes were observed during treatment with metformin. On the contrary, leptin concentrations did not show any statistically significant change during the study with any of the drugs studied here. In summary, our present results might suggest a direct inhibitory effect of androgen excess on adiponectin secretion by adipocytes in obese PCOS women, supporting the hypothesis that androgen excess contributes to adipocyte dysfunction in these women.     

Evaluation of insulin resistance and plasma levels for visfatin and resistin in obese and non-obese patients with polycystic ovary syndrome

This study was designed to evaluate insulin resistance and plasma levels of visfatin and resistin in obese and non-obese patients with polycystic ovary syndrome (PCOS).A total of 37 premenopausal PCOS patients with (n = 18, mean (SD) age: 27.5 (5.7 years) or without obesity (n = 19, mean (SD) age: 23.7 (3.1) years) and healthy volunteers (n = 18, mean (SD) age:29.8 (4.1) years) were included in this study. Data on clinical characteristics, glycemic parameters and lipid parameters were recorded for each subject as were plasma visfatin and resistin levels. Mean (SD) HOMA-IR values were significantly higher in obese PCOS patients (3.4 (1.7)) compared with non-obese PCOS patients (2.0 (1.2), p<0.01) and controls (1.6 (0.8), p<0.01). No significant difference was noted between study groups in terms of plasma resistin (ng/mL) or visfatin (ng/mL) levels. There was no correlation between serum plasma visfatin (r = 0.127, p = 0.407) and resistin (r = -0.096, p = 0.544) levels and HOMA-IR. In conclusion, our findings revealed increased likelihood of metabolic and dyslipidemic manifestations in obese compared to non-obese PCOS patients, while no significant difference was noted in visfatin and resistin levels among PCOS patients in terms of co-morbid obesity and in comparison to controls.     

多囊卵巢综合征患者阴道微生态变化及其与性激素水平的关系

目的探讨多囊卵巢综合征(PCOS)患者阴道微生态变化及其与性激素水平的关系。方法将2018年7月-2019年7月我院生殖健康与不孕症科收治的132例PCOS患者作为研究组,选择同期在我院进行妇科体检的86例健康女性作为对照组。16S rRNA法和定量PCR反应检测阴道分泌物微生态情况,放射免疫法测定血清中睾酮(T)、卵泡刺激素(FSH)、黄体生成素(LH)、雌二醇(E2)、孕酮(P)、催乳素(PRL)水平,分析微生态变化与性激素水平的关系。结果研究组患者阴道分泌物清洁度Ⅳ度检出率,滴虫、假丝酵母菌及线索细胞阳性检出率,阴道微生态失调率,血清T、LH、E2及PRL水平均高于对照组(P0.05),研究组患者血清FSH、P水平低于对照组(P0.05)。阴道微生态失调患者血清中E2水平高于阴道微生态正常患者,P水平低于阴道微生态正常患者(P0.05)。结论 PCOS患者存在阴道微生态失衡,阴道微生态的变化与血清性激素水平存在相关性,考虑激素水平的变化可能参与阴道微生态失调的发生。