Low serum hepcidin levels in women with polycystic ovary syndrome: evidence from meta-analysis

BACKGROUND

Iron metabolism plays a significant role in the development of metabolic disorders in women with polycystic ovary syndrome (PCOS). Despite the importance of hepcidin, a key iron regulator, current research on serum hepcidin levels in PCOS patients shows conflicting results.

METHODS

PubMed, Embase, Web of Science, Cochrane Library and the China National Knowledge Infrastructure (CNKI) database were systematically searched from their inception to 9 September 2023. The search aimed to identify studies in English and Chinese that examined hepcidin levels in women with PCOS compared to healthy control subjects. Standardized mean differences (SMDs) with corresponding 95% confidence intervals (95% CIs) were calculated to evaluate the difference in serum hepcidin levels between women with and without PCOS.

RESULTS

The meta-analysis included a total of 10 eligible studies, which encompassed 499 PCOS patients and 391 control subjects. The pooled analysis revealed a significant reduction in serum hepcidin levels among the PCOS patients compared to the healthy controls (SMD = -3.49, 95% CI: -4.68 to -2.30, p < .05). There was no statistically significant difference in serum hepcidin levels between PCOS patients with a body mass index (BMI) < 25 and those with a BMI ≥ 25 (p > .05).

CONCLUSION

The serum hepcidin levels of women with PCOS were significantly lower than those of healthy controls, which suggests that serum hepcidin could be a potential biomarker for PCOS.

Assessment of Serum Elements Concentration and Polycystic Ovary Syndrome (PCOS): Systematic Review and Meta-analysis

Change in the levels of trace elements has been linked with PCOS pathogenesis by various studies, whereas some had reported no such association. Therefore, in order to evaluate association of eleven trace element (Cu, Zn, Cr, Cd, Se, Mn, Fe, Mg, Co, Ni and Pb) serum concentration with PCOS pathogenesis, current systematic review and meta-analysis has been carried out. Literature search was conducted using PubMed, Central Cochrane Library, Google Scholar and Science Direct databases with appropriate keywords. Studies published upto 3rd of September were evaluated for eligibility with suitable inclusion and exclusion criteria. Only case-control studies examining the association of serum trace element concentrations between PCOS cases and controls were selected. Present meta-analysis identified 32 articles with 2317 PCOS and 1898 controls. The serum Cu (MD = 15.40; 95% CI = 4.32 to 26.48; p = 0.006), Co (MD = 0.01; 95% CI = 0.01 to 0.02; p = 0.000), Cr (MD = 0.04; 95% CI = 0.00 to 0.07; p = 0.03) and Fe (MD = 12.98; 95% CI = 5.87-20.09; p = 0.0003) concentration is significantly higher, while lower concentration has been observed for Se (MD =  - 0.99; 95% CI =  - 1.31 to - 0.67; p = 0.000) and Mg (MD =  - 223.41; 95% CI =  - 391.60 to - 55.23; p = 0.009) among women with PCOS in comparison with the healthy group. Concentration of other elements which were analysed is not significantly related to PCOS. In short, PCOS women has higher serum concentrations of Cu, Co, Cr and Fe and lower concentrations of Se and Mg. Studies with sub-population of obese, non-obese and with and without insulin resistance are important to understand the pathomechanism of these elements in the syndrome.

Relationship between serum hepcidin levels and cardiovascular disease in patients with maintenance hemodialysis

Background

To investigate the serum level of hepcidin and its relationship with cardiovascular disease (CVD) in maintenance hemodialysis (MHD) patients.

Methods

Blood was obtained from 75 MHD patients before undergoing hemodialysis and 20 healthy controls. Serum hepcidin, advanced oxidation protein products (AOPP) and interleukin (IL)-6 were measured by enzyme-linked immunosorbant assay (ELISA). Spearman correlation, and binary logistic regression linear regression analyses were used to assess the relationship between serum hepcidin and other parameters.

Results

The serum level of hepcidin, AOPP and IL-6 was significantly up-regulated in MHD patients compared with the control (P < 0.05). Furthermore, serum hepcidin levels in patients with CVD were higher than those in patients without CVD (P < 0.05). In all MHD patients, serum hepcidin level was correlated positively with erythropoietin (EPO) dose per week (ρ = 0.251, P = 0.030), EPO resistance index (ρ = 0.268, P = 0.020), ferritin (ρ = 0.814, P < 0.001), transferin saturation (TSAT, ρ = 0.263, P = 0.023), AOPP (ρ = 0.280, P = 0.049), high sensitive C reactive protein (ρ = 0.151, P = 0.006), IL-6 (ρ = 0.340, P = 0.003) and left ventricular mass index (LVMI, ρ = 0.290, P = 0.033). Moreover, it was negatively correlated with serum pre-albumin (ρ = -0.266, P = 0.021), total iron-binding capacity (TIBC, ρ = -0.458, P < 0.001), unsaturated iron-binding capacity (UIBC, ρ = -0.473, P < 0.001) and transferrin (ρ = -0.487, P < 0.001). Linear regression analysis showed that ferritin (β = 0.708, P < 0.001), TIBC (β = -0.246, P = 0.032) and IL-6 (β = 0.209, P = 0.041) were independently associated with hepcidin. Results of binary logistic regression analysis suggested that higher serum hepcidin level (>249.2 ng/mL) was positively and independently related to CVD (OR = 1.32, 95% CI [1.20-9.56], P = 0.043).

Conclusions

Serum hepcidin level is associated with CVD in MHD patients, indicating that hepcidin may be a novel biomarker and therapeutic target for CVD.

Serum ferritin as a candidate diagnostic biomarker of polycystic ovarian syndrome: a meta-analysis

Objective: In this study, we investigated about the potential of serum ferritin as a complementary diagnostic biomarker of polycystic ovarian syndrome (PCOS) by performing a meta-analysis of existing literature. Materials and methods: Eleven studies written in English were retrieved up to 30 June 2018. Data were extracted from the selected studies by two of the authors and was subjected to statistical analysis. Levels of serum ferritin were compared between women with PCOS and controls using the standardized mean difference (SMD) and 95% confidence interval (CI). Subgroup analysis was also performed and stratified by ethnicity (Asians versus Caucasians). Results: Overall post-outlier outcomes indicated that elevated serum ferritin is strongly associated with PCOS (SMD: 0.52; 95% CI: 0.40-0.64; P^A = 10^-5). Subgroup analysis by ethnicity showed no significant difference between Asian and Caucasian population. Post-outlier receiving operations characteristics curve were plotted and showed that values for serum ferritin showed good potential in discriminating patients with and without PCOS (AUC = 0.827, p = 0.006). Conclusion: Our findings suggest that high serum ferritin level is significantly associated with PCOS and its potential as a biomarker is evident in its high diagnostic accuracy. However, additional studies are needed to confirm our claims.

Evaluation of serum hepcidin and iron levels in patients with PCOS: a case-control study

PURPOSE

Polycystic ovary syndrome (PCOS) is the most common cause of chronic anovulation with a prevalence of 5-10% in women of reproductive age. The etiology of this disease is not well known, and hepcidin is one of the factors affecting the pathogenesis of the disease. The aim of this study was to evaluate plasma levels of hepcidin in patients with PCOS and its correlation with serum iron level.

METHODS

In this case-control study, plasma levels of hepcidin, IL-6, and ferritin using ELISA method and serum iron levels using a spectrophotometric method were tested on 56 women with PCOS (case group) and 41 healthy subjects (control group). The results were analyzed using t test, General Linear Model, Binary logistic regression, and linear regression tests.

RESULTS

The mean hepcidin levels were 1.97 ± 0.53 and 2.40 ± 0.25 pg/ml in the case and control groups, respectively. The t-test results showed significant difference between the two groups (p = 0.0001). The mean serum iron levels were 72.89 ± 28.97 and 70.62 ± 31.18 g/dl in the case and control groups, respectively. The t test analysis indicated no significant difference between the two groups. The serum ferritin and iron levels had no significant relation with serum hepcidin level in two groups.

CONCLUSION

Despite the differences in the serum levels of hepcidin between the two groups, no significant relation was observed between serum iron levels and hepcidin level in this group of patients. This implies the need for more comprehensive studies on gene expression in hepcidin and iron pathways using real-time and Western techniques to investigate more precisely serum hepcidin level and its relationship with the factors mentioned.

Interleukin-6 Levels in Women with Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis

Background

The change of serum interleukin-6(IL-6) levels in women with polycystic ovary syndrome (PCOS), as well as the relations between IL-6 levels and body mass index (BMI), insulin resistance(IR) and androgen status of PCOS patients, are not fully understood.

Methods

A literature search was performed in October 2015 using PubMed, Embase and the Cochrane Library databases to identify studies. Random-effects model was used to estimate the standardized mean differences (SMDs) with 95% confidence intervals (CIs).

Results

Twenty articles with 25 case-control studies included 1618 women (922 PCOS patients and 696 controls) were included in this study. IL-6 levels in controls were significantly lower than that of PCOS patients (SMD = 0.78, 95%CI = 0.41–1.16, P<0.001), with significant heterogeneity across studies (I² = 91% and P<0.001). Meta-regression analysis model indicated IR status was the main source of heterogeneity (P = 0.005). Results from group analysis suggested that high IL-6 levels in PCOS were significantly associated with Homeostasis Model Assessment of Insulin Resistance (HOMA2-IR) ratio and total testosterone ratio (T ratio), and was found in both lean and obese women with PCOS. Cumulative meta-analysis results indicated the total effect size (SMD) had tend to be stable since 2012(0.79 to 0.92).

Conclusions

A high IL-6 level is not an intrinsic characteristic of PCOS, but may be a useful monitoring biomarker for the treatment of PCOS.

GDF-15 and Hepcidin Levels in Nonanemic Patients with Impaired Glucose Tolerance

Aims. Growth Differentiation Factor-15 (GDF-15) has been suggested as one of the regulators of hepcidin, an important regulatory peptide for iron deposition. Current data is conflicting about the relationship between hepcidin and disorders of glucose metabolism. We aimed to investigate serum hepcidin and GDF-15 concentrations and their associations with each other, in nonanemic subjects with impaired glucose tolerance (IGT) in comparison with the nonanemic subjects with normal glucose tolerance (NGT). Methods. Thirty-seven subjects with IGT and 32 control subjects with NGT, who were age-, gender-, and body mass index- (BMI-) matched, were included in the study. Results. Serum GDF-15 levels were significantly higher in IGT compared to NGT. There were no differences in hepcidin, interleukin-6, and high sensitive C-reactive protein levels between the groups. We found a positive correlation between GDF-15 and hepcidin levels. There were also positive correlations between GDF-15 and age, uric acid, creatinine, and area under the curve for glucose (AUC-G). Hepcidin was correlated positively with ferritin levels. In the multiple regression analysis, GDF-15 concentrations were independently associated with age, uric acid, and AUC-G. Conclusions. Impaired glucose tolerance is associated with increased GDF-15 levels even in the absence of anemia, but the levels of hepcidin are not significantly altered in prediabetic state.

Calcium plus vitamin D supplementation influences biomarkers of inflammation and oxidative stress in overweight and vitamin D-deficient women with polycystic ovary syndrome: a randomized double-blind placebo-controlled clinical trial

OBJECTIVE

This study was conducted to determine the effects of calcium plus vitamin D supplementation on inflammatory factors and biomarkers of oxidative stress among overweight vitamin D-deficient women with polycystic ovary syndrome (PCOS).

DESIGN, PATIENTS AND MEASUREMENTS

This randomized double-blind placebo-controlled clinical trial was performed among 104 overweight vitamin D-deficient women diagnosed with PCOS aged 18-40 years. Participants were randomly divided into four groups. Group A received 1000 mg calcium daily and vitamin D placebo weekly (N = 26), group B 50000 IU vitamin D weekly and calcium placebo daily (N = 26), group C 1000 mg calcium daily plus 50000 IU vitamin D weekly (N = 26) and group D calcium placebo daily plus vitamin D placebo weekly (N = 26) for 8 weeks. Fasting blood samples were taken at baseline and 8 weeks after intervention to measure inflammatory factors and biomarkers of oxidative stress.

RESULTS

After 8 weeks, individuals taking calcium plus vitamin D supplements had greater decreases in homoeostatic model assessment beta-cell function (HOMA-B) score (-11·1 vs -8·6, -3·4 and 13·7, respectively, P = 0·03), serum high-sensitivity C-reactive protein (hs-CRP) (-948·3 vs 802·3, -383·8 and 618·2 ng/ml, respectively, P = 0·04) and plasma malondialdehyde (MDA) concentrations (-0·6 vs -0·5, -0·1 and 0·6 μmol/l, respectively, P = 0·009), and significant increases in plasma total antioxidant capacity (TAC) (35·2 vs 21·1, 22·5 and -153·8 mmol/l, respectively, P = 0·006) and glutathione (GSH) levels (216·0 vs 3·9, -47·5 and -160·8 μmol/l, respectively, P = 0·001) compared with calcium alone, vitamin D alone and placebo groups. Calcium plus vitamin D cosupplementation did not influence plasma NO and catalase levels.

CONCLUSIONS

We found that calcium plus vitamin D cosupplementation for 8 weeks among overweight and vitamin D-deficient women with PCOS had beneficial effects on inflammatory factor and biomarkers of oxidative stress.

Effect of metformin on serum interleukin-6 levels in polycystic ovary syndrome: a systematic review

Background

Most women with polycystic ovary syndrome (PCOS) have insulin resistance, hyperinsulinemia, and elevated serum IL-6 levels. These elevated IL-6 levels may have links with insulin resistance and hyperandrogenism. Metformin may have beneficial effects on the chronic low-grade inflammatory background associated with PCOS.

Methods

A systematic review was performed via PUBMED, EMBASE, and The Cochrane Library on PCOS studies published through November 30, 2013. Studies were selected that evaluated the effect of metformin on IL-6 levels in PCOS patients. Studies not containing adequate diagnosis information about PCOS or not excluding of other causes of hyperandrogenism were excluded.

Results

Five studies met the inclusion criteria. Of these, one study reported a significant decrease in IL-6 levels after metformin treatment in women with PCOS. Two studies reported that treatment-related reductions in IL-6 levels were significantly correlated with insulin metabolism. In the remaining two studies, plasma IL-6 levels did not change following metformin treatment.

Conclusions

Serum IL-6 levels of PCOS patients may be influenced by metformin. Early application of metformin therapy may relieve chronic low-grade inflammation in women with PCOS. However, further investigations with larger samples are needed to better understand the effects of metformin on IL-6 levels and chronic inflammation in PCOS.

Is pentraxin 3 a new cardiovascular risk marker in polycystic ovary syndrome?

BACKGROUND/AIMS

Polycystic ovary syndrome (PCOS) patients have an increased rate of subclinical inflammation, which plays a role in the pathogenesis of atherosclerosis. Pentraxin 3 (PTX3) is an inflammatory mediator which belongs to the same family as the well-established cardiovascular biomarker C-reactive protein (CRP). The present study was performed to investigate plasma PTX3 levels in patients with PCOS and to determine the relationship between PTX3 and other known cardiovascular risk factors.

METHODS

40 patients with PCOS and 40 age- and BMI-matched healthy controls were included in the study. The groups were divided into subgroups according to BMI. Insulin resistance indexes, lipid profile, CRP and PTX3 levels were analyzed.

RESULTS

There was no difference for insulin resistance indexes and lipid profile between the PCOS and control groups. CRP levels were significantly higher in obese PCOS and control subjects than in lean subjects, whereas no difference in PTX3 concentrations was observed between subgroups.

CONCLUSION

PTX3 and CRP levels were similar in the PCOS group compared with the non-PCOS control group.

Association between adiponectin receptor 1 gene polymorphism and insulin resistance in Chinese patients with polycystic ovary syndrome

BACKGROUND/AIMS

Adiponectin receptor 1 (ADIPOR1) is an identified receptor for adiponectin, an adipocytokine with anti-inflammatory and insulin-sensitizing properties. The ADIPOR1 gene is a potential candidate gene in polycystic ovary syndrome (PCOS). The aim of this study is to assess the association between single-nucleotide polymorphism (SNP) rs1539355 in the ADIPOR1 gene and PCOS in Chinese women.

METHODS

302 patients with PCOS and 312 healthy controls were included in this study. The ADIPOR1 genotype distribution was detected using the polymerase chain reaction melting temperature shift method.

RESULTS

The genotypic distributions of SNP rs1539355 did not differ in patients with PCOS compared to controls. However, the frequency of the G allele in the PCOS group was significantly higher than that in the control group (p = 0.037). Patients with the AG or GG genotype had a higher homeostasis model assessment for insulin resistance (HOMA-IR) (p < 0.05) compared to patients with the AA genotype. The fasting insulin levels in subjects with the GG genotype were significantly higher than those in patients with the AA genotype (p < 0.05).

CONCLUSION

SNP rs1539355 in the ADIPOR1 gene is associated with insulin resistance in Chinese PCOS patients.