Serum ghrelin, leptin and resistin levels in adolescent girls with polycystic ovary syndrome

"Association of Leptin with Polycystic Ovary Syndrome: a Systematic Review and Meta-Analysis"

Background

Serum leptin has been considered as an important measurable diagnostic and prognostic biomarker for polycystic ovarian syndrome (PCOS), although its evidence for use in clinical practice is limited. We aim to synthesize the available evidence on the clinical use of serum leptin values in PCOS by doing a systematic review and meta-analysis of studies.

Objective

To conduct a meta-analysis to determine the pooled effect size of the association of leptin levels in patients with PCOS.

Methods

We searched electronic databases, i.e., PubMed, Google Scholar, Web of Science, ClinicalTrials.gov, and Medline from inception to September 2020, keeping filters for human studies and published in the English language. We used the random-effects model if heterogeneity between the studies was > 50%; otherwise, a fixed-effect model was applied to determine the standardized mean difference with 95% CI for comparison of leptin level between cases and controls. All the statistical analyses were completed using software STATA version 13.

Results

The meta-analysis included a total of 35 studies involving 2015 cases and 1767 controls that suggested statistically significantly higher leptin levels in the women with PCOS as compared to controls (SMD, 1.76, 95% CI 1.28 to 2.23, P < 0.001). In the stratified analysis when only high methodological quality studies were included, we did not observe a statistically significant difference in the leptin level between PCOS and controls (SMD 0.68, 95% CI -0.09 to 1.46). Analysis restricted to low methodological quality studies observed statistically significant high leptin levels in PCOS women as compared to controls (SMD 2.24, 95% CI 1.65 to 2.83).

Conclusion

The available evidence suggests that elevated leptin levels may be associated with risk of PCOS as compared to controls; however, failure to observe the similar association in high methodological quality studies demands further well-designed adequately powered studies to validate the findings.

Circulating resistin and follistatin levels in obese and non-obese women with polycystic ovary syndrome: A systematic review and meta-analysis

This meta-analysis was performed to resolve the inconsistencies regarding resistin and follistatin levels in women with polycystic ovary syndrome (PCOS) by pooling the available evidence. A systematic literature search using PubMed and Scopus was carried out through November 2020 to obtain all pertinent studies. Weighted mean differences (WMDs) with corresponding 95% confidence intervals (CIs) were calculated to evaluate the strength of the association between the levels of resistin and follistatin with PCOS in the overall and stratified analysis by obesity status. A total of 47 publications, 38 for resistin (2424 cases; 1906 controls) and 9 studies for follistatin (815 cases; 328 controls), were included in the meta-analysis. Resistin levels were significantly higher in PCOS women compared with non-PCOS controls (WMD = 1.96 ng/ml; 95%CI = 1.25–2.67, P≤0.001) as well as in obese PCOS women vs. obese controls, and in non-obese PCOS women compared with non-obese controls, but not in obese PCOS vs. non-obese PCOS patients,. A significantly increased circulating follistatin was found in PCOS patients compared with the controls (WMD = 0.44 ng/ml; 95%CI = 0.30–0.58, P≤0.001) and in non-obese PCOS women compared with non-obese controls and in obese PCOS women vs. obese controls, but, no significant difference in follistatin level was observed in obese PCOS compared with non-obese PCOS women. Significant heterogeneity and publication bias was evident for some analyses. Circulating levels of resistin and follistatin, independent of obesity status, are higher in women with PCOS compared with controls, showing that these adipokines may contribute to the pathology of PCOS.

Neurotransmitter, neuropeptide and gut peptide profile in PCOS-pathways contributing to the pathophysiology, food intake and psychiatric manifestations of PCOS

Polycystic ovary syndrome (PCOS) is a major health problem with a heterogeneous hormone-imbalance and clinical presentation across the lifespan of women. Increased androgen production and abnormal gonadotropin-releasing hormone (GnRH) release and gonadotropin secretion, resulting in chronic anovulation are well-known features of the PCOS. The brain is both at the top of the neuroendocrine axis regulating ovarian function and a sensitive target of peripheral gonadal hormones and peptides. Current literature illustrates that neurotransmitters regulate various functions of the body, including reproduction, mood and body weight. Neurotransmitter alteration could be one of the reasons for disturbed GnRH release, consequently directing the ovarian dysfunction in PCOS, since there is plenty evidence for altered catecholamine metabolism and brain serotonin or opioid activity described in PCOS. Further, the dysregulated neurotransmitter and neuropeptide profile in PCOS could also be the reason for low self-esteem, anxiety, mood swings and depression or obesity, features closely associated with PCOS women. Can these altered central brain circuits, or the disrupted gut-brain axis be the tie that would both explain and link the pathogenesis of this disorder, the occurrence of depression, anxiety and other mood disorders as well as of obesity, insulin resistance and abnormal appetite in PCOS? This review intends to provide the reader with a comprehensive overview of what is known about the relatively understudied, but very complex role that neurotransmitters, neuropeptides and gut peptides play in PCOS. The answer to the above question may help the development of drugs to specifically target these central and peripheral circuits, thereby providing a valuable treatment for PCOS patients that present to the clinic with GnRH/LH hypersecretion, obesity or psychiatric manifestations.

High concentration of chemerin caused by ovarian hyperandrogenism may lead to poor IVF outcome in polycystic ovary syndrome: a pilot study

A chronic low-grade inflammation state accounts for an important part of the pathogenesis of polycystic ovary syndrome (PCOS). The adipose tissue derived cytokine chemerin has recently been proven to be a proinflammatory chemokine, but its mechanism involved in the pathogenesis of PCOS remains largely unresolved. From non-obese patients with and without PCOS, follicular fluid and granulosa cells were retrieved. The effect of testosterone on the expression of chemerin and its receptors was explored in granulosa cells. IVF outcomes in different groups based on FF-chemerin (chemerin in the follicular fluid) level were further compared. The concentration of FF-chemerin, and the mRNA expression of chemerin and its receptors in granulosa cells from PCOS were significantly higher than those from non-PCOS. FF-chemerin was positively correlative to total testosterone (TT) and luteinizing hormone (LH) in the follicular fluid. Furthermore, testosterone upregulated the expression of chemerin and its receptors in vitro. The oocyte utilization rate and high-quality embryo rate were significantly decreased in the high FF-chemerin group. The upregulated chemerin levels in the ovary of PCOS patients, which may be caused by ovarian hyperandrogenism, may be a risk factor for oocyte maturation and embryo development. These findings may provide a basis for novel interventions to improve IVF outcomes.

Linking Stress and Infertility: A Novel Role for Ghrelin

Infertility affects a remarkable one in four couples in developing countries. Psychological stress is a ubiquitous facet of life, and although stress affects us all at some point, prolonged or unmanageable stress may become harmful for some individuals, negatively impacting on their health, including fertility. For instance, women who struggle to conceive are twice as likely to suffer from emotional distress than fertile women. Assisted reproductive technology treatments place an additional physical, emotional, and financial burden of stress, particularly on women, who are often exposed to invasive techniques associated with treatment. Stress-reduction interventions can reduce negative affect and in some cases to improve in vitro fertilization outcomes. Although it has been well-established that stress negatively affects fertility in animal models, human research remains inconsistent due to individual differences and methodological flaws. Attempts to isolate single causal links between stress and infertility have not yet been successful due to their multifaceted etiologies. In this review, we will discuss the current literature in the field of stress-induced reproductive dysfunction based on animal and human models, and introduce a recently unexplored link between stress and infertility, the gut-derived hormone, ghrelin. We also present evidence from recent seminal studies demonstrating that ghrelin has a principal role in the stress response and reward processing, as well as in regulating reproductive function, and that these roles are tightly interlinked. Collectively, these data support the hypothesis that stress may negatively impact upon fertility at least in part by stimulating a dysregulation in ghrelin signaling.

Leptin Levels in Women With Polycystic Ovary Syndrome: A Systematic Review and a Meta-Analysis

OBJECTIVE

Conflicting results regarding leptin levels in women with polycystic ovary syndrome (PCOS) have been reported. We summarize all available evidence from human participant studies to evaluate leptin levels in PCOS.

DATA SOURCES

PubMed, ClinicalTrials.gov , and Web of Science databases were searched with English-language restriction for only human beings from the inception to December 31, 2015. Search terms included PCOS (polycystic ovary syndrome or PCOS) and leptin.

METHODS OF STUDY SELECTION

A total of 238 studies were reviewed, and a total of 19 studies, involving 991 women with PCOS and 898 controls, were eligible for our meta-analysis. Studies were eligible if provided leptin means and standard deviation in women with PCOS and healthy women controls.

RESULTS

Parameters, such as body mass index, insulin resistance (IR), and total testosterone, which may influence leptin levels were extracted. Data were collected and analyzed by RevMan 5.3 and Stata/SE14.0. The pooling analysis of all relevant studies revealed that leptin levels were significantly higher in patients with PCOS than in controls, with standardized mean difference of 1.62 (95% confidence interval: 1.01-2.23). However, the heterogeneity across studies was considerable and not eliminated in subgroup analyses. Meta-regression analysis further suggested that the heterogeneity might be relevant to variability in IR and study location.

CONCLUSION

Elevated leptin levels are detected in women with PCOS compared with non-PCOS controls. Higher leptin levels may be correlated with IR, metabolic disorder, infertility, and even cardiovascular disease risk in PCOS, which may contribute to the etiology and development of PCOS.

Adipokines and soluble cell adhesion molecules in insulin resistant and non-insulin resistant women with polycystic ovary syndrome

INTRODUCTION

Insulin resistance (IR) is closely associated with increased atherogenic risk.

OBJECTIVE

To investigate leptin, adiponectin, soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1) levels and their relationship with each other and metabolic parameters in women with polycystic ovary syndrome (PCOS).

METHODS

The study included 76 PCOS women divided into insulin resistant and non-insulin resistant. Anthropometric parameters, glucose and lipid parameters, leptin, adiponectin, sICAM-1 and sVCAM-1 were determined. Homeostasis model of IR index(HOMA-IR), atherogenic index of plasma(AIP) and leptin/adiponectin ratio were calculated. HOMA-IR > 2.5 and/or fasting plasma glucose/immunoreactive insulin ratio < 0.333 were used as markers for IR.

RESULTS

Non-insulin resistant PCOS had significantly higher adiponectin and sVCAM-1 levels. AIP was significantly higher in insulin resistant PCOS. Adiponectin showed a positive correlation with sVCAM-1 and sICAM-1.

CONCLUSION

Insulin resistant PCOS women were at higher atherogenic risk compared to non-insulin resistant group. sVCAM-1 data confirms the necessity of further investigations for clarifying its role in IR.

Leptin and body mass index in polycystic ovary syndrome

OBJECTIVE

Polycystic ovary syndrome (PCOS) is a common endocrine disorder associated with obesity. Human and animal studies showed a direct relationship between leptin level and obesity, however, results from different studies were mixed. This study investigated the status of leptin level in PCOS and its relationship with body mass index (BMI) in a group of Iranian women with PCOS.

METHODS

In this cross-sectional study, 40 women with PCOS and 36 healthy women were assigned to experimental and control groups, respectively. Those in the PCOS group were not prescribed any medications for 3 months prior to the study. Fasting blood samples were then collected during the 2(nd) or 3(rd) day of menstruation for laboratory measurement of serum total leptin, blood glucose (fasting blood sugar), serum insulin, follicle-stimulating hormone, and luteinizing hormone (LH).

RESULTS

Mean BMI of the PCOS and control groups were 26.62 ± 4.03 kg/m(2) and 23.52 ± 2.52 kg/m(2), respectively (P = 0.006). The mean total leptin in the PCO group was also 10.69 ± 5.37 ng/mL and 5.73 ± 2.36 ng/mL in the control group (P = 0.0001). A significant relationship was found between leptin level and BMI as well as LH level among women with PCOS (P < 0.05). However, there was no significant correlation between leptin and insulin (P > 0.05).

CONCLUSION

The results of this study indicated an increased leptin level among women with PCOS that positively associated with BMI and LH.

Low circulating ghrelin levels in women with polycystic ovary syndrome: a systematic review and meta-analysis

Although numerous, human subject studies evaluating the relationship between circulating ghrelin levels and polycystic ovary syndrome (PCOS) risk have yielded inconsistent findings. We aimed to quantitatively assess the association by summarizing all available evidence from human subject studies. The PubMed and Web of Science databases were searched up to February 2015 for eligible studies. Studies were eligible if they reported circulating ghrelin levels in women with PCOS and healthy women controls. A fixed or random-effects model was used to pool risk estimations. Twenty studies including 894 PCOS patients and 574 controls were included in the meta-analysis. The studies had fair methodological quality. The pooling analysis of all available studies revealed that ghrelin levels were significantly lower in PCOS patients than in controls, with standardized mean difference of -0.40 (95% CI: -0.73, -0.08). The significant association persisted in many subgroup strata. However, the heterogeneity across studies was considerable and not eliminated in subgroup analyses. Meta-regression analysis further suggested that the heterogeneity might be relevant to variability in study location, PCOS relevant factors like HOMA-IR ratio, as well as other factors not assessed. In conclusion, our meta-analysis suggested that ghrelin levels were significantly lower in PCOS patients than in controls. Further studies with large sample sizes are warranted to replicate our findings.

Gastrointestinal hormones and polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is an endocrine disease of women in reproductive age. It is characterized by anovulation and hyperandrogenism. Most often patients with PCOS have metabolic abnormalities such as dyslipidemia, insulin resistance, and glucose intolerance. It is not surprising that obesity is high prevalent in PCOS. Over 60 % of PCOS women are obese or overweight. Modulation of appetite and energy intake is essential to maintain energy balance and body weight. The gastrointestinal tract, where nutrients are digested and absorbed, plays a central role in energy homeostasis. The signals from the gastrointestinal tract arise from the stomach (ghrelin release), proximal small intestine (CCK release), and distal small intestine (GLP-1 and PYY) in response to food. These hormones are recognized as "appetite regulatory hormones." Weight loss is the key in the treatments of obese/overweight patients with PCOS. However, current non-pharmacologic management of body weight is hard to achieve. This review highlighted the gastrointestinal hormones, and discussed the potential strategies aimed at modifying hormones for treatment in PCOS.

Beneficial effects of pioglitazone and metformin in murine model of polycystic ovaries via improvement of chemerin gene up-regulation

Background

Polycystic ovary syndrome (PCO) is recognized as the most common endocrinopathy in female. Chemerin is a novel adipocytokine that is expressed in ovary and upregulated in adipose tissue of obese, PCO patients. To date there is no report about the regulation of ovarian chemerin gene expression after PCO induction and treatment by insulin sensitizing drugs including pioglitazone and metformin.

Thirty female rats were divided into six experimental groups with five rats in each group including control group, PCO group (i.m injection of 4 mg estradiol benzoate for 40 days), metformin treated (200 mg/kg/day for 21 days), pioglitazone treated (20 mg/kg/day, for 21 days), PCO + metformin and PCO + pioglitazone. PCO was detected by microscopic observation of vaginal smear and treatment by metformin and pioglitazone was initiated one week after that. Ovarian chemerin expression was analyzed by real time PCR and western blotting.

Results

Our results demonstrated that PCO induction resulted in elevation of chemerin mRNA and protein levels in ovary in concomitant with incidence of insulin resistance and increasing androgen and progesterone production. We observed that metformin and pioglitazone attenuated ovarian chemerin expression and improved insulin resistance and abnormal steroid production in PCO rats.

Conclusion

Based on data presented here we concluded that alteration of ovarian chemerin expression may has important role in PCO development and manipulation of chemerin expression or signaling by pioglitazone or metformin can be a novel therapeutic mechanism in the treatment of PCO patients by these drugs.

Serum leptin levels in polycystic ovary syndrome and its relationship with metabolic and hormonal profile in pakistani females

The study aimed to investigate the levels of serum leptin in PCOS females and to correlate it with metabolic and hormonal parameters. Sixty-two PCOS and ninety normal cycling (NC) females with matched age and body mass index (BMI) were recruited for this cross-sectional study. Serum leptin, FSH, LH, E2, free testosterone, progesterone, thyroid profile, and FBG levels were measured. The mean leptin levels in PCOS and NC were not significantly different (45.56 ng/mL ± 1.49 vs 41.78 ± 1.31 ng/mL, P > 0.05); however, leptin levels showed a strong correlation with BMI in PCOS and NC group (r = 0.77, P < 0.0001; r = 0.82, P < 0.0001, resp.). High E2 levels in NC had a significant correlation with leptin whereas FBG correlated with leptin in PCOS (r = 0.51, P = 0.005). TSH had a substantial correlation (r = 0.49, P < 0.005; r = 0.69, P < 0.005) in PCOS and NC, respectively. There was no significant difference found in circulating leptin concentration between PCOS and NC subjects. Leptin levels in PCOS were related with metabolic impairments manifested by disturbance in FBG levels and impairment of reproductive functions in terms of reduced E2 secretion.

The relationship between gut and adipose hormones, and reproduction

BACKGROUND

Reproductive function is tightly regulated by nutritional status. Indeed, it has been well described that undernutrition or obesity can lead to subfertility or infertility in humans. The common regulatory pathways which control energy homeostasis and reproductive function have, to date, been poorly understood due to limited studies or inconclusive data. However, gut hormones and adipose tissue hormones have recently emerged as potential regulators of both energy homeostasis and reproductive function.

METHODS

A PubMed search was performed using keywords related to gut and adipose hormones and associated with keywords related to reproduction.

RESULTS

Currently available evidence that gut (ghrelin, obestatin, insulin, peptide YY, glucagon-like peptide-1, glucose-dependent insulinotropic peptide, oxyntomodulin, cholecystokinin) and adipose hormones (leptin, adiponectin, resistin, omentin, chemerin) interact with the reproductive axis is presented. The extent, site and direction of their effects on the reproductive axis are variable and also vary depending on species, sex and pubertal stage.

CONCLUSIONS

Gut and adipose hormones interact with the reproductive axis as well as with each other. While leptin and insulin have stimulatory effects and ghrelin has inhibitory effects on hypothalamic GnRH secretion, there is increasing evidence for their roles in other sites of the reproductive axis as well as evidence for the roles of other gut and adipose hormones in the complex interplay between nutrition and reproduction. As our understanding improves, so will our ability to identify and design novel therapeutic options for reproductive disorders and accompanying metabolic disorders.

Antidepressants for polycystic ovary syndrome

BACKGROUND

The prevalence of depression in women with polycystic ovary syndrome (PCOS) is high; one study has shown it to be four times that of women without PCOS. Therefore, systematic evaluation of the effectiveness and safety of antidepressants for women with PCOS is important.

OBJECTIVES

To evaluate the effectiveness and safety of antidepressants in treating depression and other symptoms in women with PCOS.

SEARCH METHODS

We searched the following databases from inception to June 2012: the Cochrane Menstrual Disorders and Subfertility Group Trials Register, the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, PsycINFO and Chinese National Knowledge Infrastructure, the metaRegister of Controlled Trials (controlled-trials.com), the National Institute of Health Clinical Trials register (clinicaltrials.gov) and the World Health Organization International Trials Registry Platform search portal (www.who.int/trialsearch/Default.aspx).

SELECTION CRITERIA

Only randomised controlled trials (RCTs) studying the effectiveness and safety of antidepressants for women with PCOS were included in this review.

DATA COLLECTION AND ANALYSIS

The methodological quality of the trials was assessed independently by two review authors, in parallel with data extraction. The risk of bias in the included study was assessed in six domains: 1. sequence generation; 2. allocation concealment; 3. blinding of participants, personnel and outcome assessors; 4. completeness of outcome data; 5. selective outcome reporting; 6. other potential sources of bias.

MAIN RESULTS

We found no studies reporting any of our primary review outcomes (depression and allied mood disorder scores, quality of life and adverse events). Only one study with 16 women was eligible for inclusion. This study compared sibutramine versus fluoxetine in women with PCOS, and reported only endocrine and metabolic outcomes. It was unclear whether the participants had psychological problems at baseline. No significant difference was found between the groups for any of the measured outcomes.

AUTHORS' CONCLUSIONS

There is no evidence on the effectiveness and safety of antidepressants in treating depression and other symptoms in women with PCOS.

Adiponectin, leptin and ghrelin levels in obese adolescent girls with polycystic ovary syndrome

STUDY OBJECTIVE

To evaluate the differences in adipokines, namely adiponectin, leptin, and ghrelin, in obese adolescent girls with or without polycystic ovary syndrome (PCOS).

DESIGN

Case-control study.

SETTING

University hospital.

PARTICIPANTS

38 adolescent girls (age 15-20 years). Group I: 17 Obese adolescent girls with PCOS (BMI ≥ 30 kg/m(2)); Group II: Control group of 21 obese adolescent girls (BMI ≥ 30 kg/m(2)).

MAIN OUTCOME MEASURES

Adiponectin, leptin, and ghrelin measurements.

RESULTS

LH, LH/FSH, and cortisol levels were significantly higher in the obese PCOS girls compared to the obese controls (6.94 ± 3.28 vs 4.44 ± 1.79; 1.50 ± 0.72 vs 0.90 ± 0.36; 16.02 ± 4.28 vs 12.46 ± 5.29; P < .05, respectively). Adiponectin, leptin, and ghrelin levels were similar between the obese PCOS girls and the obese controls (11.13 ± 6.00 vs 15.26 ± 12.66; 23.66 ± 11.54 vs 23.11 ± 11.17; 665.69 ± 402.12 vs 650.22 ± 467.73, respectively). Adiponectin negatively correlated with BMI (r = -0.32; P = .04) and positively correlated with fasting glucose (r = 0.40; P = .01). Leptin positively correlated with BMI (r = 0.534; P = .001), estradiol (r = 0.354; P = .02), and TSH (r = 0.374; P = .02). No significant correlation was found between ghrelin and the test parameters.

CONCLUSION

Among obese adolescents with PCOS, adiponectin, and leptin levels do not seem to be determined by the existence of PCOS, while ghrelin presents no significant correlation.

Effect of short-term standard therapeutic regimens on neuropeptide Y and adipose tissue hormones in overweight insulin-resistant women with polycystic ovary syndrome

AIM

The study was aimed at elucidating the influence of a 3-month treatment with routine therapeutic regimens--oral hormonal contraceptives (OHC) with antiandrogenic activity (a standard combination of ethynil estradiol 35 microg plus cyproterone acetate 2 mg) in combination with insulin sensitizing agents--metformin (Group I) and rosiglitazone (Group II) on adipose tissue hormones and hypothalamic neuropeptide Y (NPY) in women with polycystic ovary syndrome.

PATIENTS AND METHODS

The study included 66 overweight insulin resistant women with PCOS according to the recent ESHRE-ASRM criteria randomized into 2 age-matched therapeutic groups.

RESULTS

Significant decrease of leptin (P < 0.01; P = 0.001, resp.), resistin (P < 0.01; P < 0.01, resp.), tumour necrosis factor alpha (TNF alpha) (P = 0.001; P < 0.001, resp.), and NPY (P < 0.05; P < 0.001, resp.) was observed in both groups after treatment. These findings were in parallel with a significant decrease in the anthropometric parameters of body weight in the metformin group only. No significant changes in hormonal characteristics of the groups were found except for a significant decrease in androstenedione and DHEA-S (P < 0.05) in the metformin group and in 17-OH-progesterone (P < 0.05) in the rosiglitazone group. HDL-cholesterol rose and diastolic blood pressure fell significantly (P < 0.05) in the metformin group.

CONCLUSION

Our data suggest beneficial effects of the treatment on potential cardiovascular risk in insulin resistant PCOS women.

The plasma level and gene expression of resistin in polycystic ovary syndrome

OBJECTIVES

To investigate the relationship between plasma resistin, polycystic ovary syndrome (PCOS), and insulin resistance (IR). To compare the mRNA level of resistin in mononuclear cells and monocyte-derived macrophages in women with PCOS and controls.

MATERIALS AND METHODS

Patients with PCOS and controls were enrolled and IR was considered as the stratified factor for subgroups. Fasting blood was collected to determine the levels of sex hormones, insulin, glucose, blood lipid, and resistin. Resistin gene expression was evaluated by quantitative real-time RT-PCR in mononuclear cells and monocyte-derived macrophages cultured with or without rosiglitazone for 96 h.

RESULTS

No significant difference of plasma resistin levels was found among PCOS-IR, PCOS-non-IR, control-IR, and control-non-IR groups. There were no significant differences in resistin mRNA expression between participants with and without PCOS and with and without IR. Resistin mRNA expression in monocyte-derived macrophages was higher than that in mononuclear cells (p = 0.04), and could be reduced by rosiglitazone (p < 0.001).

CONCLUSIONS

Plasma resistin does not correlate with normal weight PCOS or IR. Resistin gene expression in mononuclear cells and monocyte-derived macrophages in PCOS and IR is the same as controls. Further researches on the role of resistin in the pathogenesis of PCOS or IR should concentrate on the tissue level.

Ghrelin and reproductive disorders

Ghrelin is an important factor involved in most of the metabolic and hormonal signals which adapt the reproductive functions in conditions of altered energy balance. Moreover, the coordinated role of leptin and ghrelin appears in fact to have a specific role in the regulation of puberty. Systemic action of ghrelin on the reproductive axis involves the control of the hypothalamic-pituitary-gondal axis. In addition, it has been shown that ghrelin may directly act at a gonadal level in both females and males. Available data also demonstrate that sex steroid hormones and gonadotropins may in turn regulate the gonadal effect of ghrelin, as documented by studies performed in females with the polycystic ovary syndrome and in hypogonadal men. Notably, recent studies also confirm a potentially important role for ghrelin in fetal and neonatal energy balance, and specifically in allowing fetal adaptation to an adverse intrauterine environment.

IL-6 serum levels and production is related to an altered immune response in polycystic ovary syndrome girls with insulin resistance

Polycystic ovarian syndrome (PCOS) is frequently characterized by obesity and metabolic diseases including hypertension, insulin resistance, and diabetes in adulthood, all leading to an increased risk of atherosclerosis. The present study aimed to evaluate serum and production of inflammatory markers in adolescent Sardinian PCOS. On the basis of HOMA findings, patients were divided into noninsulin resistant (NIR) and insulin resistant (IR), and were weight- and age-matched with healthy girls. Inflammatory cytokines (TNF-α, IL-6, Il-10, TGF-β) and lipokines (leptin, adiponectin), the reactant hs-CRP, and in vitro inflammatory lympho-monocyte response to microbial stimulus were evaluated. In healthy and PCOS subjects, leptin and hs-CRP were correlated with BMI, whereas adiponectin was significantly reduced in all PCOS groups. Although cytokines were similar in all groups, Interleukin-6 (IL-6) was significantly higher in IR PCOS. Moreover, in the latter group lipopolysaccharide-activated monocytes secreted significantly higher levels of IL-6 compared to NIR and control subjects. To conclude, IR PCOS displayed increased IL-6 serum levels and higher secretion in LPS-activated monocytes, whilst revealing no differences for other inflammatory cytokines. These results suggest that in PCOS patients an altered immune response to inflammatory stimuli is present in IR, likely contributing towards determining onset of a low grade inflammation.

Characteristics of polycystic ovarian syndrome and relationship with ghrelin in adolescents

OBJECTIVE

Some points of pathogenesis in polycystic ovarian syndrome (PCOS) are still unknown. In this study we evaluated the characteristics of this disease and its relationship with ghrelin in adolescence.

DESIGN

A prospective case control study was designed. Four groups: obese PCOS (n = 13), lean PCOS (n = 13), obese control (n = 10) and lean control (n = 10) were formed. Oral glucose tolerance tests (OGTT) were performed on all subjects. Laboratory and clinical features of groups were compared.

SETTING

University pediatric endocrinology clinic.

PARTICIPANTS

Adolescents with PCOS.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Insulin resistance, ghrelin, delta ghrelin (difference of ghrelin between basal and 120(th) minute after OGTT), androgens

RESULTS

Insulin resistance ratios were 93.3%, 46.6%, 50% in obese PCOS, lean PCOS and obese controls respectively. Ghrelin levels were lower in obese PCOS group but statistically different only between obese and lean PCOS groups. Ghrelin was correlated negatively with HOMA-IR (P < 0.001), 17 OH progesterone (P = 0.05), total (P = 0.015) and free testosterone (P = 0.013). Ghrelin suppression was blunted in PCOS groups. Ghrelin suppression ratios after glucose load were 24.4%, 28.7%, 36%, 35% obese PCOS, lean PCOS, obese control and lean control groups respectively.

CONCLUSION

Low ghrelin levels in obese PCOS patients, correlations between insulin resistance, androgens and ghrelin, blunted suppression of ghrelin after glucose load in PCOS have been considered as evidences of ghrelin role in pathogenesis of this syndrome.

Adipose tissue, metabolic syndrome and polycystic ovary syndrome: from pathophysiology to treatment

In the last few years, polycystic ovary syndrome (PCOS) has deserved major attention because it is linked to the same cluster of events that promote the metabolic syndrome. This review will point out the relationships between fat excess, insulin resistance and the metabolic syndrome. Adipocytes are actually considered as endocrine cells that synthesize and release molecules (adipokines) that play an endocrine/paracrine role, such as adiponectin, atrial natriuretic peptide, leptin, resistin, tumour necrosis factor alpha (TNFalpha). Metabolic syndrome is a chronic low-grade inflammatory condition in which adipokines play a major role. Isolated adipocytes from women with PCOS express higher mRNA concentrations of some adipokines involved in cardiovascular risk and insulin resistance. However, environmental factors and lifestyle play a major role in determining the appearance of the phenotypes of PCOS. In morbid obese women with PCOS, bariatric surgery decreases bodyweight and fat excess and reverses hyperandrogenism and sterility. In lean or overweight women with PCOS, changes in lifestyle in combination with drugs reducing visceral fat and insulin resistance reverse the symptoms and signs of PCOS. Promising treatments for PCOS seem to be insulin sensitizers such as metformin and glitazones.