Plasma visfatin levels in normal weight women with polycystic ovary syndrome

BACKGROUND: The present study was designed to measure plasma visfatin levels in normal weight women with polycystic ovary syndrome (PCOS) and to assess possible correlations between visfatin and the hormonal or metabolic parameters of the syndrome. METHODS: Twenty-five normal weight [body mass index (BMI)<25 kg/m(2)] women with PCOS, 24 obese and overweight (BMI>25 kg/m(2)) controls (ovulating women without clinical or biochemical hyperandrogenism), and 24 normal weight controls were studied. Blood samples were collected between the 3rd and the 7th days of a menstrual cycle in the control groups and during a spontaneous bleeding episode in the PCOS groups at 9:00 A.M., after an overnight fast. Circulating levels of LH, FSH, prolactin (PRL), testosterone (T), Delta(4)-androstenedione (Delta(4)-Alpha), dehydroepiandrosterone sulfate (DHEA-S), 17alpha-OH-progesterone (17OH-P), sex hormone-binding globulin (SHBG), insulin, glucose, and visfatin were measured. RESULTS: Plasma visfatin levels and the visfatin-to-insulin ratio were significantly lower in normal weight controls than in both normal weight women with PCOS and overweight or obese controls. The visfatin-to-insulin ratio was significantly higher in normal weight women with PCOS than in overweight or obese controls. Plasma visfatin levels were found to be positively correlated with LH and Delta(4)A levels, as well as with free androgen index (FAI) values, and negatively correlated with SHBG. LH and SHBG levels were found to be the only independent significant determinants of circulating visfatin. In the control groups, plasma visfatin levels were significantly correlated with BMI, waist (W) measurement, and waist-to-hip ratio (WHR). CONCLUSIONS: Visfatin levels are positively associated with obesity in healthy women of reproductive age. Moreover, the present study indicates, for the first time, a possible involvement of increased visfatin levels in PCOS-associated metabolic and hormonal disturbances.     

Adiponectin levels in women with polycystic ovary syndrome

Serum adiponectin levels were evaluated in 60 women with polycystic ovary syndrome (PCOS), 30 normal-weighted and 30 obese women, and 60 healthy women age and body mass index (BMI) matched with the patients. The homeostasis model assessment (HOMA) score was also calculated. Both in PCOS and controls, serum adiponectin levels were significantly (P < 0.05) lower in obese than normal-weight women, without any difference between PCOS and controls. The HOMA score was significantly (P < 0.05) higher in obese than normal-weight women both in PCOS and controls; additionally, the HOMA score was significantly (P < 0.05) higher in normal-weight PCOS than normal-weight controls. Both in PCOS and controls, adiponectin levels were significantly correlated with BMI (r = -0.51, P < 0.01 in PCOS; r = -0.45, P < 0.01 in controls) and HOMA values (r = -0.39, P < 0.05 in PCOS; r = -0.35, P < 0.05 in controls); HOMA was correlated with BMI (r = 0.51, P < 0.01 in PCOS, r = 0.61, P < 0.001 in controls). In conclusion, our results confirm that adiponectin concentrations change according to variations of fat mass. They further suggest that insulin sensitivity per se probably does not play any pivotal role in the control of adiponectin levels in PCOS women.     

多囊卵巢综合征性激素水平检测

目的：探讨血清性激素各项检测指标与不同年龄段的多囊卵巢综合征（PCOS）患者的关系及其临床意义。方法：以月经周期正常的健康妇女为对照组,采用化学发光法测定30岁以下年龄组和30岁及以上年龄组PCOS患者促黄体生成素（LH）、促卵泡生成素（FSH）、泌乳素（PRL）、雌二醇（E2）、睾酮（TESTO）、孕酮（Prog）水平,通过统计学软件进行比较分析。结果：多囊卵巢综合征患者,30岁以下年龄组和30岁及以上年龄组LH高于对照组（P〈0．01）,E2高于对照组（P〈0．05）,TESTO高于对照组（P〈0．01）。30岁以下PCOS患者组和30岁及以上PCOS患者组各检测指标之间差异无统计学意义（P〉0．05）。结论：血清中LH,E2高水平及TESTO增高可能是多囊卵巢综合征的预示因子,高LH、高E2、高雄激素血症可能是引起PCOS发生的因素之     

Normal endothelial function despite insulin resistance in healthy women with the polycystic ovary syndrome

Women with the polycystic ovarian syndrome (PCOS) carry a number of cardiovascular risk factors, including insulin resistance, lipid abnormalities, and an altered pattern of sex steroid exposure. Noninvasive measurements of endothelial function, which can demonstrate abnormalities well in advance of clinically apparent disease, have not been previously reported in this patient group. We undertook a cross-sectional evaluation of endothelium-dependent and -independent vascular function using brachial artery ultrasound. We studied healthy women with clinical and laboratory evidence of PCOS (n = 18) and age-matched controls (n = 19), not taking any antihypertensive, cholesterol-lowering, or hormonal therapies. Laboratory parameters of insulin resistance, glycemia, cholesterol status, and hormone levels were also measured. Despite marked differences in glucose/insulin ratio [6.1 +/- 1.1 mmol/pmol (PCOS) vs. 9.9 +/- 0.6 (controls)] and free androgen index [11.9 +/- 2.3 (PCOS) vs. 3.7 +/- 0.6 (controls); normal, <5], we did not find evidence of impaired endothelial function in our patients with PCOS. Both endothelium-dependent (8.7 +/- 3.1%) and endothelium-independent (23.2 +/- 3.4%) vascular responses were normal, and practically identical to the responses seen in the control group (endothelium-dependent, 9.0 +/- 0.7; endothelium-independent, 23.0 +/- 1.2%). The PCOS women were more obese, but baseline brachial arterial diameters were not different between groups. There was no correlation between degree of insulin resistance or hyperandrogenism and the brachial response. This group of healthy obese young women with insulin resistance and hyperandrogenism due to PCOS had normal endothelium-dependent and -independent vascular responses compared to age-matched controls. The factors resulting in preservation of these response are unclear and warrant further investigation.     

Predictors of endothelial dysfunction in young women with polycystic ovary syndrome

CONTEXT: Women with polycystic ovary syndrome (PCOS) may be at increased risk for cardiovascular disease. Endothelial dysfunction is an early marker of atherosclerosis. OBJECTIVES: The objectives of this study were to 1) compare endothelial function in young women with PCOS and regularly menstruating control women, and 2) to identify the determinants of endothelial function and investigate its relationship with body mass index in women with PCOS. DESIGN: This was a cross-sectional study. SETTING: This study was conducted at a tertiary cardiovascular research center. PATIENTS: Sixty-two young women with PCOS (mean age, 22.7 yr) and 17 control women, matched as a group for age and body mass index, were studied. Twenty-three women with PCOS were lean, 21 were overweight, and 18 were obese. MAIN OUTCOME MEASURES: Endothelium-dependent and -independent vascular function was assessed by measuring flow-mediated dilation (FMD) and nitrate-mediated dilation in the brachial artery (diameter change during hand hyperemia and after sublingual glyceryl trinitrate administration, respectively). RESULTS: FMD and nitrate-mediated dilation were significantly lower in PCOS than in control women (reduced by approximately 50 and 25%, respectively; both P < 0.0005). Insulin resistance, total testosterone, and total cholesterol were independent predictors of FMD, accounting for 21, 10, and 9% of the variance, respectively (P < 0.005 for all). A trend of deterioration in FMD from lean to overweight and obese PCOS women was observed, but differences among groups were not statistically significant. CONCLUSIONS: Women with PCOS have significant endothelial dysfunction at an early age (i.e. early 20s), and largely independent of obesity. This suggests that women with PCOS are at increased risk for early onset cardiovascular disease and may gain particular benefit from measures to improve endothelial function.     

Early impairment of endothelial structure and function in young normal-weight women with polycystic ovary syndrome

The aim of this study was to evaluate the presence of early vascular damage in young normal-weight women with polycystic ovary syndrome (PCOS).Thirty young normal-weight women with PCOS, who had no additional metabolic or cardiovascular diseases, and 30 healthy women (controls) matched for age and body mass index were studied. A complete hormonal assay was performed in each subject. Serum insulin and glucose levels were measured at baseline and after the oral glucose tolerance test. Plasma endothelin-1 levels and serum lipid profile were also assessed. The endothelial function was studied by flow-mediated dilation on the brachial artery, and arterial structure was evaluated by intima-media thickness measurement using Doppler ultrasound of both common carotid arteries.A significant (P < 0.05) difference in flow-mediated dilation (14.3 +/- 1.9% vs. 18.1 +/- 2.0% for PCOS patients and controls, respectively) and in intima-media thickness (0.53 +/- 0.09 mm vs. 0.39 +/- 0.08 mm for PCOS patients and controls, respectively) was found between PCOS and control subjects. Serum endothelin-1 levels were also significantly (P < 0.05) higher in PCOS patients compared with controls (1.1 +/- 0.4 pmol/liter vs. 0.5 +/- 0.2 pmol/liter for PCOS patients and controls, respectively).In conclusion, our data show that young, normal-weight, nondyslipidemic, nonhypertensive women with PCOS have an early impairment of endothelial structure and function.     

Metformin therapy improves coronary microvascular function in patients with polycystic ovary syndrome and insulin resistance

BACKGROUND: Women with polycystic ovary syndrome (PCOS) are thought to have increased cardiovascular risk. Metformin therapy reduces whole-body insulin resistance (IR) in patients with type-2 diabetes mellitus (DM). OBJECTIVE: As insulin resistance accompanying PCOS may be reversed by metformin therapy, we hypothesized that metformin therapy might improve coronary microvascular functions in women with PCOS and IR. PATIENTS AND METHODS: We treated 16 women with PCOS and IR with metformin, and measured coronary flow reserve (CFR) at the beginning and after 6 months of metformin therapy using transthoracic second-harmonic Doppler echocardiography. RESULTS: At the end of the 6 months of metformin therapy, baseline coronary diastolic peak flow velocity (DPFV) did not change significantly (from 24.6 +/- 4.3 to 23.0 +/- 3.1, P = 0.106); however, hyperaemic coronary DPFV (from 68.2 +/- 12.7 to 74.5 +/- 9.7, P = 0.08), and CFR (from 2.75 +/- 0.48 to 3.3 +/- 0.5, P = 0.016) was significantly improved by metformin therapy. CONCLUSION: In women with PCOS, coronary microvascular function and CFR are significantly improved by 6 months of therapy with metformin.     

Altered vascular function in young women with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is characterized by hyperinsulinemic insulin resistance, a metabolic disorder that in other circumstances is associated with increased cardiovascular risk. We compared macrovascular and microvascular function in 19 women with PCOS with 12 control subjects matched as a group for body mass index. Macrovascular function was assessed by recording pulse wave velocity (PWV) across the aorta and brachial artery. Microvascular function was studied by wire myography, by measuring the concentration response curve to norepinephrine (NE) before and after incubation with insulin (100 and 1,000 pM). PWV at the level of the brachial artery was found to be significantly elevated in the PCOS group [9.08 (range, 8.34-11.15) m/sec(-1) vs. 8.27 (range, 7.5-9.01) m/sec(-1); P = 0.03]. In contrast, PWV measured in the aorta did not differ between the two groups [7.49 +/- 1.21 vs. 7.84 +/- 1.44 m/sec(-1); P = 0.8]. In vessels from control subjects, insulin reduced the contraction response to NE. At an insulin concentration of 100 pM, NE negative log EC50 (pD(2)) was 6.2 +/- 0.24 vs. 6.7 +/- 0.15 (P = 0.02). At a concentration of 1,000 pM, NE pD(2) was 6.4 +/- 0.14 vs. 6.9 +/- 0.19 (P = 0.0006). Both concentrations also caused attenuation in maximal tension developed in response to NE (insulin 100 pM, 12 +/- 3%, P = 0.002; insulin 1,000 pM, 17 +/- 5%, P = 0.009). In contrast, there was no change in the PCOS group with insulin at 100 pM for either pD(2) (6.7 +/- 0.24 vs. 6.8 +/- 0.27; P = 0.3) or maximum contraction (-0.4 +/- 2%; P = 0.8). At 1,000 pM, there was a change in pD(2) (6.4 +/- 0.2 vs. 6.8 +/- 0.2; P = 0.003) but not maximum contraction (4 +/- 3%; P = 0.2). In conclusion, this study is the first to demonstrate increased vascular stiffness and a functional defect in the vascular action of insulin ex vivo in patients with PCOS. We suggest that these findings are indicative of insulin resistance at a vascular level in women without overt cardiovascular disease.     

Decreased soluble leptin receptor levels in women with polycystic ovary syndrome

OBJECTIVE: Polycystic ovary syndrome (PCOS) is associated with insulin resistance and a high incidence of obesity. Leptin, the product of the ob gene, is involved in the regulation of energy balance and obesity and circulates in both free and bound forms. The soluble leptin receptor (sOB-R) is the most important leptin-binding protein, thus influencing the biologically active free leptin level. DESIGN: We assessed the correlation of metabolic and endocrine parameters with leptin and sOB-R levels in 122 PCOS women (aged 27 +/- 5.7 years) and 81 healthy controls (aged 25 +/- 4.0 years). METHODS: Leptin and sOB-R levels were measured using ELISA kits. In addition, anthropometric variables, body fat and endocrine parameters were evaluated and a glucose tolerance test performed to assess indices of insulin resistance and glucose metabolism. RESULTS: In PCOS patients, no correlation was found between leptin or sOB-R and parameters of hyper-androgenism. However, as expected, body mass index (BMI), body fat, waist circumference and indices of insulin resistance were significantly correlated with leptin in PCOS subjects and controls. In a subgroup analysis of lean, overweight and obese PCOS patients, significant differences were found in leptin (29.7 +/- 20.7 vs 45.4 +/- 25.0 vs 67.7 +/- 28.8 ng/ml, P < 0.0001) and sOB-R (8.0 +/- 3.4 vs 6.4 +/- 2.5 vs 5.7 +/- 2.3 ng/ml, P < 0.05). Compared with BMI-matched controls, lean PCOS patients had lower sOB-R levels (8.0 +/- 3.4 vs 12.7 +/- 4.7 ng/ml, P < 0.0001) and higher free leptin indices (4.5 +/- 3.9 vs 2.8 +/- 2.2, P = 0.0285). CONCLUSION: Taking into account that low sOB-R levels supposedly compensate diminished leptin action, PCOS per se might cause leptin resistance.     

Exercise training improves autonomic function and inflammatory pattern in women with polycystic ovary syndrome (PCOS)

Background Polycystic ovary syndrome (PCOS) is a common female reproductive‐age endocrine disease predominantly characterized by chronic anovulation, hyperandrogenism, insulin‐resistance and low‐grade inflammatory status. Exercise training (ET) favourably modulates cardiopulmonary function and insulin‐sensitivity markers in PCOS women. The present study investigated the effects of ET on autonomic function and inflammatory pattern in PCOS women. Study design Prospective baseline uncontrolled clinical study. Methods One‐hundred and eighty five PCOS women referred to our department were screened for the inclusion into the study protocol from March 2004 to July 2007. One‐hundred and twenty four PCOS women met the criteria for the inclusion into the study protocol and were subdivided into two groups each composed of 62 patients: PCOS‐T (trained) group underwent 3‐month ET program, whereas PCOS‐UnT (untrained) group did not. At baseline and at 3‐month follow‐up, hormonal and metabolic profile, cardiopulmonary parameters, autonomic function (as expressed by heart rate recovery, HRR) and inflammatory pattern [as expressed by C‐reactive protein (CRP) and white blood cells (WBCs) count] were evaluated. Results PCOS‐T showed a significant (P < 0·05) improvement in maximal oxygen consumption (VO_2max) and in post‐exercise HRR, and a significant (P < 0·001) decrease in CRP and WBCs; whereas no statistically significant changes of the same parameters were observed in PCOS‐UnT. Multiple linear regression analysis showed that 3‐month HRR is linearly related to the inclusion in training group (β = 0·316, P < 0·001), VO_2max (β = 0·151, P = 0·032) and the ratio between glucose and insulin area under curve (AUC) (β = 0·207, P = 0·003), and inversely related to body mass index (β = –0·146, P = 0·046), insulin AUC (β = –0·152, P = 0·032), CRP (β = –0·165, P < 0·021), and WBCs count (β = –0·175, P = 0·039). Conclusions Exercise training improves autonomic function and inflammatory pattern in PCOS women.     

Metformin reduces serum C-reactive protein levels in women with polycystic ovary syndrome

Low-grade chronic inflammation, reflected in elevated levels of serum C-reactive protein (CRP), has recently been linked to obesity, insulin resistance syndromes such as polycystic ovary syndrome (PCOS), and an increased risk of cardiovascular disease. Because the insulin sensitizer metformin has been shown to improve metabolic disturbances in PCOS, it was of particular interest to examine serum CRP levels during metformin therapy. Twenty nonobese women [body mass index (BMI) /==" BORDER="0"> 27 kg/m(2)) with PCOS were randomized to receive either metformin (500 mg twice daily for 3 months, then 1000 mg twice daily for 3 months) or ethinyl estradiol (35 micro g)-cyproterone acetate (2 mg) oral contraceptive pills. The serum concentrations of CRP were significantly higher in obese than in nonobese subjects at baseline [4.08 +/- 0.53 (SE) vs. 1.31 +/- 0.28 mg/liter; P < 0.001] and correlated to BMI and to a lesser extent waist-hip ratio, suggesting that the elevated CRP levels may be related to obesity and not only to PCOS itself. During metformin treatment, serum CRP levels decreased significantly from 3.08 +/- 0.7 mg/liter to 1.52 +/- 0.26 mg/liter at 6 months in the whole study population (P = 0.006) and especially in obese subjects. In contrast, the treatment with ethinyl estradiol-cyproterone acetate increased serum CRP levels from 2.91 +/- 0.68 mg/liter to 4.58 +/- 0.84 mg/liter (P < 0.001). Whether this effect is related to estrogen action in the liver or whether it reflects increased inflammation process and possible risks for cardiovascular disease remains unclear. The decrease of serum CRP levels during metformin therapy is in accordance with the known beneficial metabolic effects of this drug and suggests that CRP or other inflammation parameters could be used as markers of treatment efficiency in women with PCOS.     

Dissociation of endothelial function and arterial stiffness in nonobese women with polycystic ovary syndrome (PCOS)

Objective Polycystic ovary syndrome (PCOS) is associated with cardiovascular risk but it is not clear if this is independent of obesity and insulin resistance. This study therefore investigates endothelial function and arterial stiffness in nonobese, noninsulin resistant women with PCOS. Design This is cross‐sectional case–control study. Patients A total of 19 young women with PCOS, with body mass index (BMI) <30 kg/m², and 19 healthy controls matched for age and BMI were included in the study. Measurements Endothelial function was assessed with flow mediated dilatation (FMD) of the brachial artery, while arterial stiffness was assessed with pulse wave velocity (PWV) and augmentation index (AI). Results There were no significant differences between PCOS and control subjects when assessing the following clinical and biochemical variables: blood pressure, homeostasis model assessment insulin‐resistance index, lipids and oestradiol. Women with PCOS had higher free androgen index scores (5·14 ± 3·47 vs. 3·25 ± 1·42, P = 0·036). The PCOS subjects had significantly lower FMD of the brachial artery compared with the controls (6·5 ± 2·9%vs. 10·5 ± 4·0%, P < 0·01). There were no significant differences in markers of arterial stiffness (PWV 5·8 ± 1·1 vs. 6·0 ± 1·0, P = 0·58, AI 16·5 ± 10·2 vs. 20·3 ± 10·2, P = 0·25). Conclusions Women with polycystic ovary syndrome who are young, nonobese, and have no biochemical evidence of insulin resistance, have abnormal vascular function, but normal arterial stiffness, when compared with age and weight matched control subjects. Whether this leads to a greater risk of cardiovascular disease requires further investigation.