Microvascular dysfunction in women with polycystic ovary syndrome

Ischemia but no obstructive coronary artery disease: more than meets the eye

Symptomatic women with angina are more likely to have ischemia with no obstructive coronary arteries (INOCA) compared to men. In both men and women, the finding of INOCA is not benign and is associated with adverse cardiovascular events, including myocardial infarction, heart failure and angina hospitalizations. Women with INOCA have more angina and a lower quality of life compared to men, but they are often falsely reassured because of a lack of obstructive coronary artery disease (CAD) and a perception of low risk. Coronary microvascular dysfunction (CMD) is a key pathophysiologic contributor to INOCA, and non-invasive imaging methods are used to detect impaired microvascular flow. Coronary vasospasm is another mechanism of INOCA, and can co-exist with CMD, but usually requires invasive coronary function testing (CFT) with provocation testing for a definitive diagnosis. In addition to traditional heart disease risk factors, inflammatory, hormonal and psychological risk factors that impact microvascular tone are implicated in INOCA. Treatment of risk factors and use of anti-atherosclerotic and anti-anginal medications offer benefit. Increasing awareness and early referral to specialized centers that focus on INOCA management can improve patient-oriented outcomes. However, large, randomized treatment trials to investigate the impact on major adverse cardiovascular events (MACE) are needed. In this focused review, we discuss the prevalence, pathophysiology, presentation, diagnosis and treatment of INOCA.

Impaired peripheral microvascular reactivity in patients with nonobstructive coronary artery disease

OBJECTIVE

This study aimed to determine whether peripheral microvascular reactivity is impaired in patients with nonobstructive coronary artery disease (NOCAD).

METHODS

Stable patients presenting with angina were recruited and, based on results from coronary angiography, were categorized into OCAD (coronary stenosis of ≥50%) and NOCAD (stenosis <50%) groups. A control group with no history of angina was also recruited. Forearm skin microvascular reactivity was measured using the laser Doppler blood perfusion monitor and the process of postocclusive skin reactive hyperemia (PORH).

RESULTS

Patients were categorized into OCAD (n = 42), NOCAD (n = 40), and control (n = 39) groups. Compared with the control group, the PORH perfusion percent change (PORH% change) was significantly lower in the OCAD and NOCAD groups. No significant differences were noted between the OCAD and NOCAD groups. Additionally, the NOCAD group without any coronary obstruction takes a longer time to reach peak perfusion and had lower PORH% change compared with the nonangina control group.

CONCLUSION

Angina patients with NOCAD have microvascular dysfunction as demonstrated by reduced magnitude of reperfusion with an ischemic stimulus. NOCAD patients without coronary obstruction also displayed a slower response to reperfusion.

Assessment of Early Markers of Cardiovascular Risk in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a heterogeneous syndrome, with long-term sequelae from birth to senescence. The long-term effects of PCOS are attributed to several metabolic aberrations ensuing the syndrome. In a systematic review of literature regarding the cardiovascular risk factors that accompany PCOS, we found that macrovascular function has been assessed by flow-mediated dilatation (FMD), microvascular function by venous occlusion plethysmography (VOP), and arterial structure by ultrasonographic assessment of intima-media thickness (IMT) usually of the carotid artery. Contradictory results have been reported; however, in most studies, endothelial dysfunction, an early marker of atherosclerosis assessed either by haemodynamic methods such as FMD or by biochemical methods such as endothelin-1 levels, was found to be impaired. VOP is a less-studied method, with few indices altered. IMT was found to be altered in most of the included studies, but the population was more heterogeneous. Inflammatory markers, including C-reactive protein, were also found to be altered in most studies. On the other hand, a number of interventions have been shown beneficial for the markers of cardiovascular risk, in the context of insulin-sensitizers. However, other interventions such as oral contraceptive pills or statins did not consistently show a similar beneficial effect. In summary, the early identification and eventual treatment of cardiovascular clinical and biochemical risk factors may be used in clinical practice to prevent potential 'silent' triggers of cardiovascular disease.

Assessment of Early Markers of Cardiovascular Risk in Polycystic Ovary Syndrome

Collapse

Sex differences in non-obstructive coronary artery disease

Ischaemic heart disease is a leading cause of morbidity and mortality in both women and men. Compared with men, symptomatic women who are suspected of having myocardial ischaemia are more likely to have no obstructive coronary artery disease (CAD) on coronary angiography. Coronary vasomotor disorders and coronary microvascular dysfunction (CMD) have been increasingly recognized as important contributors to angina and adverse outcomes in patients with no obstructive CAD. CMD from functional and structural abnormalities in the microvasculature is associated with adverse cardiac events and mortality in both sexes. Women may be particularly susceptible to vasomotor disorders and CMD due to unique factors such as inflammation, mental stress, autonomic, and neuroendocrine dysfunction, which predispose to endothelial dysfunction and CMD. CMD can be detected with coronary reactivity testing and non-invasive imaging modalities; however, it remains underdiagnosed. This review focuses on sex differences in presentation, pathophysiologic risk factors, diagnostic testing, and prognosis of CMD.

Intraovarian vascular enhancement via stromal injection of platelet-derived growth factors: Exploring subsequent oocyte chromosomal status and in vitro fertilization outcomes

The inverse correlation between maternal age and pregnancy rate represents a major challenge for reproductive endocrinology. The high embryo ploidy error rate in failed in vitro fertilization (IVF) cycles reflects genetic misfires accumulated by older oocytes over time. Despite the application of different follicular recruitment protocols during IVF, gonadotropin modifications are generally futile in addressing such damage. Even when additional oocytes are retrieved, quality is frequently poor. Older oocytes with serious cytoplasmic and/or chromosomal errors are often harvested from poorly perfused follicles, and ovarian vascularity and follicular oxygenation impact embryonic chromosomal competency. Because stimulation regimens exert their effects briefly and immediately before ovulation, gonadotropins alone are an ineffective antidote to long-term hypoxic pathology. In contrast, the tissue repair properties (and particularly the angiogenic effects) of platelet-rich plasma (PRP) are well known, with applications in other clinical contexts. Injection of conventional PRP and/or its components (e.g., isolated platelet-derived growth factors as a cell-free substrate) into ovarian tissue prior to IVF has been reported to improve reproductive outcomes. Any derivative neovascularity may modulate oocyte competence by increasing cellular oxygenation and/or lowering concentrations of intraovarian reactive oxygen species. We propose a mechanism to support intrastromal angiogenesis, improved follicular perfusion, and, crucially, embryo ploidy rescue. This last effect may be explained by mRNA upregulation coordinated by PRP-associated molecular signaling, as in other tissue systems. Additionally, we outline an intraovarian injection technique for platelet-derived growth factors and present this method to help minimize reliance on donor oocytes and conventional hormone replacement therapy.

Effects of Insulin Resistance on Myocardial Blood Flow and Arterial Peripheral Circulation in Patients with Polycystic Ovary Syndrome

OBJECTIVE

Polycystic ovary syndrome (PCOS) is associated with increased risk for cardiovascular disease. We sought to evaluate the effects of insulin resistance (IR) on myocardial microcirculation and peripheral artery function in patients with PCOS.

METHODS

We studied 55 women (28 with PCOS without IR, 18 with PCOS and IR and 11 normal controls) who underwent laboratorial analysis, high-resolution vascular ultrasound and real time myocardial contrast echocardiography (RTMCE). Intima-media thickness (IMT) and brachial artery flow-mediated dilation (FMD) were evaluated by vascular ultrasound. The replenishment velocity (β), plateau of acoustic intensity (A) and myocardial blood flow reserve (MBFR) were determined by quantitative dipyridamole stress RTMCE.

RESULTS

β reserve in group PCOS + IR was lower than control (2.34 ± 0.55 vs. 3.60 ± 0.6; P < 0.001) and than PCOS without IR (2.34 ± 0.55 vs. 3.17 ± 0.65; P < 0.001). MBFR in patients with PCOS without IR did not differ from those of control (4.59 ± 1.59 vs. 5.30 ± 1.64; P = 0.22) or from patients with PCOS + IR (4.59 ± 1.59 vs. 3.70 ± 1.47; P = 0.07). When comparing with control group, patients with PCOS + IR had lower MBFR (5.30 ± 1.64 vs. 3.70 ± 1.47; P = 0.01). No significant differences were found between control, PCOS without IR and PCOS + IR for FMD (0.18 ± 0.05, 0.15 ± 0.04 and 0.13 ± 0.07; P =NS) or IMT (0.48 ± 0.05, 0.47 ± 0.05 and 0.49 ± 0.07; P = NS).

CONCLUSION

Women with PCOS and IR had depressed β and MBFR as demonstrated by quantitative RTMCE, but no alteration in endothelial dysfunction or IMT. PCOS without IR showed isolated depression in β reserve, probably an earlier marker of myocardial flow abnormality.

Nonobese Young Females with Polycystic Ovary Syndrome have Nutritive Microvascular Dysfunction: A Pilot Study

OBJECTIVE

To investigate nutritive microvascular function in young nonobese females with polycystic ovary syndrome (PCOS) and to correlate microvascular reactivity with sex steroids, inflammatory markers, and metabolic variables.

METHODS

Fourteen nonobese females with PCOS (24.6 ± 2.7 years, body mass index [BMI] 23.7 ± 3.1 kg/m2) and 13 age- and BMI-matched controls (22.8 ± 2.3 years, 22.5 ± 3.4kg/m2) underwent anthropometric, hormonal, and microvascular evaluations. The main outcome measures were capillary density, red blood cell velocity (RBCV) at resting and peak during postocclusive reactive hyperemia (RBCVmax), and time taken to reach RBCVmax (TRBCVmax).

RESULTS

Subjects with PCOS had lower RBCV and higher TRBCVmax compared to controls, respectively (0.237 [0.220-0.324] vs. 0.362 [0.297-0.382] mm/s, P<.01) and (5 [5-6] vs. 4 [3-5] s, P<.05]. The free androgen index (FAI) and sex hormone-binding globulin (SHBG) level were different between groups. FAI correlated to RBCVmax (ρ = -0.49, P<.05) and to TRBCVmax (ρ = 0.41, P<.05). SHBG correlated with RBCVmax (ρ = 0.52, P<.01) while estradiol (E2) levels correlated with RBCV (ρ = 0.80, P<.001) and RBCVmax (ρ = 0.46, P<.05).

CONCLUSION

Microvascular dysfunction characterized by reduced RBCVmax and prolonged TRBCVmax was present in young, nonobese PCOS subjects. FAI was associated with observed impairments, suggesting a possible common mechanism linking sex hormones and microvascular dysfunction.

Lower-limb veins are thicker and vascular reactivity is decreased in a rat PCOS model: concomitant vitamin D3 treatment partially prevents these changes

Polycystic ovary syndrome (PCOS) causes vascular damage to arteries; however, there are no data for its effect on veins. Our aim was to clarify the effects of dihydrotestosterone (DHT)-induced PCOS both on venous biomechanics and on pharmacological reactivity in a rat model and to test the possible modulatory role of vitamin D3 (vitD). PCOS was induced in female Wistar rats by DHT treatment (83 μg/day, subcutaneous pellet). After 10 wk, the venous biomechanics, norepinephrine (NE)-induced contractility, and acetylcholine-induced relaxation were tested in saphenous veins from control animals and from animals treated with DHT or DHT with vitD using pressure angiography. Additionally, the expression levels of endothelial nitric oxide synthase (eNOS) and cyclooxygenase (COX-2) were measured using immunohistochemistry. Increased diameter, wall thickness, and distensibility as well as decreased vasoconstriction were detected after the DHT treatment. Concomitant vitD treatment lowered the mechanical load on the veins, reduced distensibility, and resulted in vessels that were more relaxed. Although there was no difference in the endothelial dilation tested using acetylcholine (ACh), the blocking effect of N(G)-nitro-l-arginine methyl ester (l-NAME) was lower and was accompanied by lower COX-2 expression in the endothelium after the DHT treatment. Supplementation with vitD prevented these alterations. eNOS expression did not differ among the three groups. We conclude that the hyperandrogenic state resulted in thicker vein walls. These veins showed early remodeling and altered vasorelaxant mechanisms similar to those of varicose veins. Alterations caused by the chronic DHT treatment were prevented partially by concomitant vitD administration.

Insulin resistance is associated with lower acetylcholine-induced microvascular reactivity in nondiabetic women

BACKGROUND

The association between insulin resistance and microvascular dysfunction is well established in obese individuals with type 2 diabetes. It is unclear whether this relationship is dependent on obesity and body fat in insulin-resistant persons. This study investigated acetylcholine (ACh)-induced microvascular reactivity in apparently healthy women (n=37, 20-45 years), with and without insulin resistance.

METHODS

Body fat mass (dual X-ray absorptiometry), waist circumference (WC), blood pressure, fasting glucose, insulin, and free fatty acid concentrations were measured. Insulin resistance was estimated using homeostasis model assessment of insulin resistance (HOMA-IR), and subjects were divided into insulin-resistant (IR, n=16) and insulin-sensitive (IS, n=21) groups. ACh-induced forearm microvascular reactivity was measured by laser Doppler imagery using iontophoresis of ACh and compared between groups adjusting for WC and skin resistance (SR).

RESULTS

The IR group had a higher body mass index (BMI) (30.7 ± 6.4 vs. 22.9 ± 7.3 kg/m(2), P < 0.01), fat mass (34.7 ± 11.9 vs. 19.7 ± 9.6 kg, P < 0.01), WC (89.9 ± 13.6 vs. 74.4 ± 9.7 cm, P < 0.01), and a lower SR (0.24 ± 0.08 vs. 0.32 ± 0.08 Ω, P < 0.05) than the IS group. Microvascular reactivity, expressed as percentage increase in perfusion from baseline, was significantly lower in IR subjects after adjusting for differences in WC and SR (420.9 ± 166.5 vs. 511.6 ± 214.8%, P < 0.05). There were associations between microvascular reactivity and SR (r=-0.34, P < 0.05) and systolic blood pressure (r=-0.36, P < 0.05), but not BMI, body fat mass, WC, or HOMA-IR.

CONCLUSION

ACh-induced microvascular reactivity was different between IR and IS apparently healthy, nondiabetic women once differences in WC and SR were accounted for.

Androgens influence microvascular dilation in PCOS through ET-A and ET-B receptors

Hyperandrogenism and vascular dysfunction often coexist in women with polycystic ovary syndrome (PCOS). We hypothesized that testosterone compromises cutaneous microvascular dilation in women with PCOS via the endothelin-1 ET-B subtype receptor. To control and isolate testosterone's effects on microvascular dilation, we administered a gonadotropin-releasing hormone antagonist (GnRHant) for 11 days in obese, otherwise healthy women [controls, 22.0 (4) yr, 36.0 (3.2) kg/m(2)] or women with PCOS [23 (4) yr, 35.4 (1.3) kg/m(2)], adding testosterone (T; 2.5 mg/day) on days 8-11. Using laser Doppler flowmetry and cutaneous microdialysis, we measured changes in skin microcirculatory responsiveness (ΔCVC) to local heating while perfusing ET-A (BQ-123) and ET-B (BQ-788) receptor antagonists under three experimental conditions: baseline (BL; prehormone intervention), GnRHant (day 4 of administration), and T administration. At BL, ET-A receptor inhibition enhanced heat-induced vasodilation in both groups [ΔCVC control 2.03 (0.65), PCOS 2.10 (0.25), AU/mmHg, P < 0.05]; ET-B receptor inhibition reduced vasodilation in controls only [ΔCVC 0.98 (0.39), 1.41 (0.45) AU/mmHg for controls, PCOS] compared with saline [ΔCVC controls 1.27 (0.48), PCOS 1.31 (0.13) AU/mmHg]. GnRHant enhanced vasodilation in PCOS [saline ΔCVC 1.69 (0.23) AU/mmHg vs. BL, P < 0.05] and abolished the ET-A effect in both groups, a response reasserted with T in controls. ET-B receptor inhibition reduced heat-induced vasodilation in both groups during GnRHant and T [ΔCVC, controls: 0.95 (0.21) vs. 0.51 (13); PCOS: 1.27 (0.23) vs. 0.84 (0.27); for GnRHant vs. T, P < 0.05]. These data demonstrate that androgen suppression improves microvascular dilation in PCOS via ET-A and ET-B receptors.

Nitric oxide-mediated cutaneous microvascular function is impaired in polycystic ovary sydrome but can be improved by exercise training

Polycystic ovary syndrome (PCOS) is associated with cardiovascular disease. The contribution of the nitric oxide (NO) dilator system to cutaneous endothelial dysfunction is currently unknown in PCOS. Our aim was to examine whether women with PCOS demonstrate impaired cutaneous microvascular NO function and whether exercise training can ameliorate any impairment. Eleven women with PCOS (age, 29 ± 7 years; body mass index, 34 ± 6 kg m(-2)) were compared with six healthy obese control women (age, 29 ± 7 years; body mass index, 34 ± 5 kg m(-2)). Six women with PCOS (30 ± 7 years; 31 ± 6 kg m(-2)) then completed 16 weeks of exercise training. Laser Doppler flowmetry, combined with intradermal microdialysis of l-N(G)-monomethyl-l-arginine, a nitric oxide antagonist, in response to incremental local heating of the forearm was assessed in women with PCOS and control women, and again in women with PCOS following exercise training. Cardiorespiratory fitness, homeostasis model assessment for insulin resistance, hormone and lipid profiles were also assessed. Differences between women with PCOS and control women and changes with exercise were analysed using Student's unpaired t tests. Differences in the contribution of NO to cutaneous blood flow [expressed as a percentage of maximal cutaneous vasodilatation (CVCmax)] were analysed using general linear models. At 42°C heating, cutaneous NO-mediated vasodilatation was attenuated by 17.5%CVCmax (95% confidence interval, 33.3, 1.7; P = 0.03) in women with PCOS vs. control women. Exercise training improved cardiorespiratory fitness by 5.0 ml kg(-1) min(-1) (95% confidence interval, 0.9, 9.2; P = 0.03) and NO-mediated cutaneous vasodilatation at 42°C heating by 19.6% CVCmax (95% confidence interval, 4.3, 34.9; P = 0.02). Cutaneous microvascular NO function is impaired in women with PCOS compared with obese matched control women but can be improved with exercise training.

Analysis of the vascular responses in a murine model of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of there productive age, but the exact pathophysiological mechanisms involved remain unclear. Cardiovascular disease risk is increased in PCOS patients and endothelial damage has been observed. We recently developed a mouse model of PCOS with reproductive and metabolic characteristics resembling those observed in women with PCOS. In this model we studied vascular function with particular emphasis on markers of vascular endothelial function. Animals were treated for 90 days with dihydrotestosterone (DHT; 27.5 mg/day) or placebo using subcutaneous continuous-release pellets. Aortas were isolated for isometric force recordings in organ baths to investigate endothelial and vascular smooth muscle characteristics. Lungs were used to analyze endothelial nitric oxide synthase (eNOS) expression and phosphorylation. Asymmetric dimethylarginine (ADMA) levels were investigated in serum to assess endothelial damage. Expression of androgen receptor (Ar) mRNA was studied in aortas. DHT treatment (compared with placebo) induced i) a significant decrease in acetylcholine-induced aortic relaxations, with no change in calcitonin gene related peptide- or sodium nitroprusside-induced relaxations, as well as 5-hydroxytryptamine-induced contractions; ii) no change in eNOS expression/phosphorylation in lungs or in plasma ADMA levels; and iii) a twofold increase in aortic AR expression. Our results suggest that, in DHT-exposed mice, hyperandrogenemia specifically decreases endothelium dependent vasorelaxation without deterioration of smooth muscle function. This study may initiate further investigations to elucidate underlying mechanism for the phenotype that is present in these animals, as well as in PCOS patients.

Polycystic Ovary Syndrome and Chronic Inflammation: Pharmacotherapeutic Implications

Objective:

To examine the relationship between polycystic ovary syndrome (PCOS), cardiovascular risk factors, cardiovascular disease (CVD), and chronic inflammation and analyze data regarding pharmacologic therapies that are recommended to reduce CVD risk in PCOS and the impact of those therapies on chronic inflammation.

Data Sources:

A search of MEDLINE (1950-October 2011) was conducted to identify clinical studies pertaining to the identification and treatment of CVD and chronic low-grade inflammation in PCOS, Search terms included polycystic ovary syndrome, cardiovascular disease, inflammation, metformin, thiazolidinedione, and statin. Bibliographies of these studies and review articles were also examined.

Study Selection and Data Extraction:

English-language clinical studies evaluating the effect of metformin, thiazolidinediones, and statins on inflammatory markers, endothelial function, adhesion molecules, fibrinolysis, cytokines, and adipokines in PCOS were included.

Data Synthesis:

Women with PCOS have an increased prevalence of many cardiovascular risk factors including obesity, android fat distribution, insulin resistance, impaired glucose tolerance, diabetes, dyslipidemia, hypertension, and metabolic syndrome. Markers of chronic low-grade inflammation, which are associated with an increased risk of CVD, are also elevated in PCOS. Clinical guidelines recommend the use of insulin sensitizers and statins to prevent CVD in some patients with PCOS. Current literature indicates that each of these medication classes has beneficial effects on inflammation, as well. Although there are currently no studies to determine whether these treatments decrease CVD in PCOS, it can be hypothesized that drugs impacting chronic inflammation may reduce cardiovascular risk. Some studies show that metformin, thiazolidinediones, and statins have beneficial effects on inflammatory markers in PCOS; however, the data are inconsistent.

Conclusions:

There is insufficient information to recommend any pharmacologic therapies for their antiinflammatory effects in PCOS in the absence of other indications such as diabetes and dyslipidemia.

Myeloperoxidases and polycystic ovary syndrome

New biological markers are emerging trying to identify earlier cardiovascular high risk subjects. Myeloperoxidases have been involved in the role of atherosclerosis process, by the beginning of the endothelial dysfunction up to the plaque rupture and clinical manifestation, and it has been demonstrated that this enzyme has also a prognostic value. We aimed to assess myeloperoxidases levels in patients with polycystic ovary syndrome (PCOS) with insulin resistance (IR), considering that these women represent a high risk group for cardiovascular disease. We developed a transversal study, comprising 26 patients with PCOS and IR and 30 controls (PCOS without IR). IR was considered with HOMA-IR ≥3.0. IR absence was considered when HOMA-IR <3.0, triglycerides <200, BMI <28.7, and BMI<27.8 in patients with familial history of type 2 diabetes. All patients went through anamnesis, physical examination, transvaginal ultrasound, and blood samples. IR PCOS patients had higher levels of myeloperoxidase (22.3 × 18.1, p = 0.047), and also higher BMI. Myeloperoxidase levels correlated directly with insulin. In conclusion, IR PCOS young patients have higher myeloperoxidase levels.

Arteriolar insulin resistance in a rat model of polycystic ovary syndrome

OBJECTIVE

To investigate the vascular dysfunction caused by insulin resistance in polycystic ovary syndrome (PCOS) and the effectiveness of vitamin D in an animal model.

DESIGN

Controlled experimental animal study.

SETTING

Animal laboratory at a university research institute.

ANIMAL(S)

Thirty female Wistar rats.

INTERVENTION(S)

Rats were divided into groups at age 21-28 weeks. Twenty of them were subjected to dihydrotestosterone (DHT) treatment (83 μg/d); ten of them also received parallel vitamin D treatment (120 ng/100 g/wk). Oral glucose tolerance tests with insulin level measurements were performed. Gracilis arterioles were tested for their contractility as well as their nitric oxide (NO)-dependent and insulin-induced dilation using pressure arteriography.

MAIN OUTCOME MEASURE(S)

Several physiologic parameters, glucose metabolism, and pressure arteriography.

RESULT(S)

DHT treatment increased the passive diameter of resistance arterioles, lowered norepinephrine-induced contraction (30.1 ± 4.7% vs. 8.7 ± 3.6%) and reduced acetylcholine-induced (122.0 ± 2.9% vs. 48.0 ± 1.4%) and insulin-induced (at 30 mU/mL: 21.7 ± 5.3 vs. 9.8 ± 5.6%) dilation. Vitamin D treatment restored insulin relaxation and norepinephrine-induced contractility; in contrast, it failed to alter NO-dependent relaxation.

CONCLUSION(S)

In DHT-treated rats, in addition to metabolically proven insulin resistance, decreased insulin-induced vasorelaxation was observed and was improved by vitamin D treatment without affecting NO-dependent relaxation. The reduction in insulin-induced dilation of arterioles is an important as yet undescribed pathway of vascular damage in PCOS and might explain the clinical effectiveness of vitamin D treatment.

Microvascular dysfunction: a direct link among BMI, waist circumference and glucose homeostasis in young overweight/obese normoglycemic women?

OBJECTIVE

Capillary recruitment is impaired in obesity (OB), possibly worsening glucose and insulin availability to target organs. In this study, we investigated whether functional microvascular parameters were correlated with clinical-anthropometrical data and whether these parameters would influence OB-related metabolic disorders, especially glucose homeostasis, in young overweight (OW)/obese women.

DESIGN

Cross-sectional clinical study of microvascular reactivity in young OW/obese women.

SUBJECTS AND METHODS

A total of 10 lean (23.1 + or - 3.2 years, body mass index (BMI) 22.3 + or - 1.6 kg m(-2)) and 42 OW/obese (24.9 + or - 3.5 years; BMI 34.5 + or - 5.7 (25.7-46.5) kg m(-2)) sedentary non-smoking women were evaluated. Lipid profile, fasting plasma glucose (PG), post-load PG (75 g-2 h), insulin, C-reactive protein, HOMA-IR (homeostasis model assessment for insulin resistance) index and anthropometric variables (weight, BMI, waist and hip circumferences, waist-to-hip ratio and blood pressure (BP)) were determined. Functional microvascular parameters (functional capillary density, red blood cell velocity at baseline and peak (RBCV(max)), and time taken to reach RBCV(max) (TRBCV(max)) during post-occlusive reactive hyperemia after 1 min arterial occlusion) were evaluated by nailfold videocapillaroscopy.

RESULTS

The time taken to reach RBCV(max) was significantly longer in OW/obese patients compared with control subjects (8.6 + or - 2.4 versus 5.7 + or - 1.1 s, P<0.001), and its delay was directly associated with adiposity levels, systolic BP and insulin resistance, and inversely related to high-density lipoprotein-cholesterol. Post-load PG could be correlated with TRBCV(max) (R = 0.48, P<0.05) and RBCV(max) (R = -0.29, P<0.05), and it was influenced by weight, waist circumference and TRBCV(max) (adjusted R(2) = 24%) as well.

CONCLUSIONS

In the investigated group of young OW/obese women, the direct correlation between post-load PG and TRBCV(max) links microvascular parameters with metabolic variables and suggests a key role for microcirculation in OB-related metabolic disorders.

Insulin sensitizers for women with polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS) is the most frequent endocrine disorder and most common cause of anovulation in women of reproductive age. It is a heterogeneous disorder, characterized by excess androgen, ovulatory dysfunction and/or polycystic ovaries. The syndrome is known for its association with several reproductive problems, including infertility and obstetric adverse effects. In addition, significant long-term health problems have been strongly linked to PCOS, with women suffering from the disorder having a significantly higher risk of diabetes, cardiovascular risk and some types of cancer, such as endometrial cancer. Although its etiology is unknown, insulin resistance is believed to play a pivotal role in its pathophysiology, with insulin sensitizers found to provide an exciting option in managing health problems associated with PCOS. Almost a decade ago, we proposed a non-insulin-sensitizing mechanism of action for insulin sensitizers through their effect on steroidogenesis. Accumulating evidence supported such an assumption, with solid evidence for a modulating effect on steroidogenesis by metformin and glitazones in the ovaries, adrenal glands and fat cells. Furthermore, other exciting positive roles for insulin sensitizers, in particular glitazones, have been reported at the level of endothelial function. Studying the value of insulin sensitizers in preventing long-term health problems in women with PCOS is still in the stage of infancy.

Hemodynamic alterations and wall properties in large arteries of young, normotensive, and non-obese women with polycystic ovary syndrome

Young, normotensive, and non-obese women with polycystic ovary syndrome (PCOS) may present abnormal hemodynamic alterations (HA). The purpose of this study was to investigate heart rate (HR), intima-media thickness (IMT), and diameter (DCCA) in the common carotid arteries (CCA), flow velocities, and resistance index in both extracranial carotid and vertebral arteries (VA), in the abdominal aorta (AO) and in the renal arteries (RA) in PCOS women and matched controls. This was a case-control study conducted at a tertiary University Hospital. We studied 53 PCOS women and 53 healthy matched volunteers as controls. The previously reported parameters were assessed using color Doppler ultrasonography. HR, IMT in the CCA, and peak systolic velocity in all examined arteries were significantly increased in PCOS women compared to controls. On the contrary, DCCA was significantly decreased in PCOS women compared to controls. End diastolic velocity (EDV) in both VA and RA, in the AO and in the left extracranial carotid system was significantly increased in the PCOS group compared to controls. Furthermore, the peripheral resistance (PR) of AO and right external carotid artery was also found to be increased while in both RA and in left VA, PR was decreased. No further statistical significant HA in EDV and PR were noted. The results of this study provide evidence for a mild hyperdynamic circulation in young, normotensive, non-obese women with PCOS compared to controls, indicating a mild sympathetic activation at an early age, which may be an underlying cause of hypertension and cardiovascular risk.

Obese but not normal-weight women with polycystic ovary syndrome are characterized by metabolic and microvascular insulin resistance

CONTEXT

Polycystic ovary syndrome (PCOS) and obesity are associated with diabetes and cardiovascular disease, but it is unclear to what extent PCOS contributes independently of obesity.

OBJECTIVE

The objective of the study was to investigate whether insulin sensitivity and insulin's effects on the microcirculation are impaired in normal-weight and obese women with PCOS.

DESIGN AND POPULATION

Thirty-five women with PCOS (19 normal weight and 16 obese) and 27 age- and body mass index-matched controls (14 normal weight and 13 obese) were included. Metabolic Insulin sensitivity (isoglycemic-hyperinsulinemic clamp) and microvascular insulin sensitivity [endothelium dependent (acetylcholine [ACh])] and endothelium-independent [sodium nitroprusside (SNP)] vasodilation with laser Doppler flowmetry was assessed at baseline and during hyperinsulinemia.

MAIN OUTCOME MEASURES

Metabolic insulin sensitivity (M/I value) and the area under the response curves to ACh and SNP curves were measured to assess microcirculatory function at baseline and during insulin infusion (microvascular insulin sensitivity).

RESULTS

Obese women were more insulin resistant than normal-weight women (P < 0.001), and obese PCOS women were more resistant than obese controls (P = 0.02). In contrast, normal-weight women with PCOS had similar insulin sensitivity, compared with normal-weight women without PCOS. Baseline responses to ACh showed no difference in the four groups. ACh responses during insulin infusion were significantly greater in normal-weight PCOS and controls than in obese PCOS and controls. PCOS per se had no significant influence on ACh responses during insulin infusion. During hyperinsulinemia, SNP-dependent vasodilatation did not significantly increase, compared with baseline in the four groups.

CONCLUSION

PCOS per se was not associated with impaired metabolic insulin sensitivity in normal-weight women but aggravates impairment of metabolic insulin sensitivity in obese women. In obese but not normal-weight women, microvascular and metabolic insulin sensitivity are decreased, independent of PCOS. Therefore, obese PCOS women in particular may be at increased risk of metabolic and cardiovascular diseases.

Metformin and oral contraceptive treatments reduced circulating asymmetric dimethylarginine (ADMA) levels in patients with polycystic ovary syndrome (PCOS)

There is a little information in literature about circulating asymmetric dimethylarginine (ADMA) concentrations in polycystic ovary syndrome (PCOS) and the results reported are discrepant. In this study, therefore, we aimed (1) to determine the circulating ADMA concentrations in 44 women with PCOS and 22 age- and BMI-matched healthy controls, (2) to evaluate its correlations with insulin resistance, gonadotrophins, and androgen secretion, and (3) to compare effects of metformin and ethinyl estradiol-cyproterone acetate (EE/CPA) treatments on circulating ADMA concentrations. In conclusion, our data indicate that circulating ADMA concentrations in non-obese, non-hypertensive and young women with PCOS are significantly higher than healthy controls and they improved by a 3-month course of metformin and oral contraceptive treatments.

Itchy-dry eye associated with polycystic ovary syndrome

PURPOSE

The authors aimed to define the ocular symptomatology of women with polycystic ovaries and hyperandrogenism.

DESIGN

Prospective, observational case series.

METHODS

Of the 62 consecutive patients with an ultrasonographic diagnosis of polycystic ovary (PCO), 16 were identified as having clinical and biochemical signs of hyperandrogenism. All women with a history of ocular symptoms (20/62 total patients [32.3%], 15/16 polycystic ovary syndrome (PCOS) patients [93.7%], and 5/46 PCO patients [10.8%]) underwent a complete eye examination with conjunctival impression cytologic sampling. Clinical measurements of tear function (tear film break-up time [BUT], Schirmer I test) were completed along with analysis of conjunctival goblet cell number, conjunctival immunostaining, and reverse-transcriptase polymerase chain reaction for the mucins MUC1 and MUC5AC. Clinical, histologic, and biochemical data of patients with PCOS were compared statistically with that of patients with PCO and with eight age- and gender-matched healthy controls. Eight of the most severely affected patients received systemic antiandrogen therapy and underwent further ocular evaluation four months after systemic therapy.

RESULTS

Women with PCOS had greater conjunctival hyperemia (P < .001), dryness (P < .001), itching (P < .001), mucous discharge (P < .001), and contact lens intolerance (P < .001) than patients with PCO. Patients with PCOS had a significant reduction of the tear film BUT accompanied by a significant increase in goblet cell number and conjunctival MUC5AC messenger ribonucleic acid expression compared with both PCO patients and healthy subjects.

CONCLUSIONS

Evaluation of the ocular surface should be considered in patients with PCO or PCOS. Women with PCOS were more likely to have itchy-dry eyes, decreased tear film BUT, and increased goblet cell density.

Vascular dysfunction during pregnancy in women with polycystic ovary syndrome

BACKGROUND

An association has been proposed between polycystic ovary syndrome (PCOS) and pregnancy-induced hypertensive disorders. Ambulatory blood pressure and carotid artery elasticity were therefore prospectively investigated in matched PCOS and control pregnancies.

METHODS

Twenty-two PCOS-control subject pairs with singleton pregnancies, matched for age, body mass index, parity and ethnicity, were recruited in the first trimester (T1, 11-13 weeks). Ambulatory blood pressure recording for 24 h and carotid artery ultrasound for elasticity estimation were performed in T1 and in the second (T2, 22-24 weeks) and third (T3, 32-34 weeks) trimesters.

RESULTS

At nearly all time points during gestation, ambulatory systolic, diastolic and mean arterial pressures were elevated in PCOS versus control pregnancies. Carotid artery stiffness index was greater and compliance was less in PCOS pregnancies compared with controls. Differences in night-time systolic pressure and carotid artery elasticity were greatest in T3. PCOS also increased the incidence of pregnancy-induced hypertension (6 of 22 cases versus 0 of 22 in controls; P = 0.011).

CONCLUSIONS

Pregnant women with PCOS have higher baseline ambulatory blood pressure and impaired arterial elasticity, suggestive of disturbed vascular adaptation to pregnancy.

Aortic function is compromised in a rat model of polycystic ovary syndrome

BACKGROUND

Arterial mechanical parameters are modified in women with polycystic ovary syndrome (PCOS), before and during pregnancy. This study tested the hypothesis that aortic mechanics and endothelial function are modified in the mifepristone-treated rat model of PCOS.

METHODS

Female rats injected daily with mifepristone or vehicle for 7-9 days were assessed by ultrasound to allow estimation of aortic stiffness index and compliance. The influence of acetylcholine (ACh) and sodium nitroprusside (SNP) on dissected phenylephrine-contracted aortic rings was assessed.

RESULTS

Aortic compliance was reduced by 67% in mifepristone-treated rats versus controls (P<0.05), while stiffness index was increased 2.3-fold (P<0.02). ACh-induced dilation was less in aortic rings from mifepristone-treated rats (P=0.022) and was less sensitive to the nitric oxide (NO) synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) (P<0.001), while SNP-induced dilation was greater (P=0.001).

CONCLUSIONS

Aortic mechanics in vivo and endothelial function in vitro were consistently perturbed in mifepristone-treated rats. Aortic ring behaviour suggested that NO release was depressed or degradation elevated, with a compensatory increase in NO sensitivity and/or activation of a non-NO-mediated relaxation mechanism. The mifepristone-treated rat is a valid model for investigation of the vascular deficits seen in PCOS.