Association of serum glypican-4 levels with cardiovascular risk predictors in women with polycystic ovary syndrome - a pilot study

Galanin and glypican-4 levels depending on metabolic and cardiovascular risk factors in patients with polycystic ovary syndrome

OBJECTIVE

Galanin is a neuropeptide which has effects not only on metabolic syndrome but also on reproduction. Glypican-4 is an adipokine associated with insulin sensitivity by interacting directly with the insulin receptor. This study evaluated serum concentrations of galanin and glypican-4 in relation with the hormonal profile as well as metabolic and cardiovascular risk factors in patients with and without polycystic ovary syndrome (PCOS).

METHODS

A total of 44 women with PCOS and 44 age-matched controls were eligible. Hirsutism scores, hormonal profile, metabolic and cardiovascular risk factors as well as galanin and glypican-4 levels were evaluated in each subject.

RESULTS

Women with PCOS exhibited lower levels of galanin (20.2 pg/mL versus 26.4 pg/mL, p = 0.002) and higher concentrations of glypican-4 (3.1 ng/mL versus 2.6 ng/mL, p < 0.001) than controls. Both adipokines were correlated positively with body mass index (BMI), insulin, triglyceride and Homeostasis Model Assessment (HOMA) index; glypican-4 also showed positive correlations with fasting blood glucose, free testosterone, modified Ferriman-Gallwey scores (p < 0.05). Multiple Linear Regression analyses showed that PCOS and BMI were the best predictors affecting galanin levels with a decreasing and increasing effect respectively; however BMI was the best predictor affecting glypican-4 levels with an increasing effect (p < 0.001).

CONCLUSION

Galanin levels were lower and glypican-4 levels were higher in women with PCOS than controls. Further studies are needed to determine whether these adipokines could be used as additional markers for insulin sensitivity and lipid profile and whether they might play a role in the pathogenesis of PCOS, in which metabolic cardiovascular risks are increased.

Imaging-Based Body Fat Distribution in Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis

BACKGROUND

Women with polycystic ovary syndrome (PCOS) are generally considered to be central obese and at higher risks of metabolic disturbances. Imaging methods are the golden standards for detecting body fat distribution. However, evidence based on magnetic resonance imaging (MRI) and computed tomography (CT) is conflicting. This study systematically reviewed the imaging-based body fat distribution in PCOS patients and quantitatively evaluated the difference in body fat distribution between PCOS and BMI-matched controls.

METHODS

PUBMED, EMBASE, and Web of Science were searched up to December 2019, and studies quantitatively compared body fat distribution by MRI, CT, ultrasound, or X-ray absorptiometry (DXA) between women with PCOS and their BMI-matched controls were included. Two researchers independently reviewed the articles, extract data and evaluated the study quality based on Newcastle-Ottawa Scale (NOS).

RESULTS

47 studies were included in systematic review and 39 were eligible for meta-analysis. Compared to BMI-matched controls, higher accumulations of visceral fat (SMD 0.41; 95%CI: 0.23-0.59), abdominal subcutaneous fat (SMD 0.31; 95%CI: 0.20-0.41), total body fat (SMD 0.19; 95% CI: 0.06-0.32), trunk fat (SMD 0.47; 95% CI: 0.17-0.77), and android fat (SMD 0. 36; 95% CI: 0.06-0.66) were identified in PCOS group. However, no significant difference was identified in all the above outcomes in subgroups only including studies using golden standards MRI or CT to evaluate body fat distribution (SMD 0.19; 95%CI: -0.04-0.41 for visceral fat; SMD 0.15; 95%CI: -0.01-0.31 for abdominal subcutaneous fat). Moreover, meta-regression and subgroup analyses showed that young and non-obese patients were more likely to accumulate android fat.

CONCLUSIONS

PCOS women seem to have abdominal fat accumulation when compared with BMI-matched controls. However, MRI- and CT- assessed fat distribution was similar between PCOS and controls, suggesting central obesity may be independent of PCOS. These findings will help us reappraise the relationship between PCOS and abnormal fat deposition and develop specialized lifestyle interventions for PCOS patients.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, identifier CRD42018102983.

Emerging Role of Adipocyte Dysfunction in Inducing Heart Failure Among Obese Patients With Prediabetes and Known Diabetes Mellitus

Adipose tissue dysfunction is a predictor for cardiovascular (CV) events and heart failure (HF) in patient population with obesity, metabolic syndrome, and known type 2 diabetes mellitus. Previous preclinical and clinical studies have yielded controversial findings regarding the role of accumulation of adipose tissue various types in CV risk and HF-related clinical outcomes in obese patients. There is evidence for direct impact of infiltration of epicardial adipocytes into the underlying myocardium to induce adverse cardiac remodeling and mediate HF development and atrial fibrillation. Additionally, perivascular adipocytes accumulation is responsible for release of proinflammatory adipocytokines (adiponectin, leptin, resistin), stimulation of oxidative stress, macrophage phenotype switching, and worsening vascular reparation, which all lead to microvascular inflammation, endothelial dysfunction, atherosclerosis acceleration, and finally to increase in CV mortality. However, systemic effects of white and brown adipose tissue can be different, and adipogenesis including browning of adipose tissue and deficiency of anti-inflammatory adipocytokines (visfatin, omentin, zinc-α2-glycoprotein, glypican-4) was frequently associated with adipose triglyceride lipase augmentation, altered glucose homeostasis, resistance to insulin of skeletal muscles, increased cardiomyocyte apoptosis, lowered survival, and weak function of progenitor endothelial cells, which could significantly influence on HF development, as well as end-organ fibrosis and multiple comorbidities. The exact underlying mechanisms for these effects are not fully understood, while they are essential to help develop improved treatment strategies. The aim of the review is to summarize the evidence showing that adipocyte dysfunction may induce the onset of HF and support advance of HF through different biological mechanisms involving inflammation, pericardial, and perivascular adipose tissue accumulation, adverse and electrical cardiac remodeling, and skeletal muscle dysfunction. The unbalancing effects of natriuretic peptides, neprilysin, and components of renin–angiotensin system, as exacerbating cause of altered adipocytokine signaling on myocardium and vasculature, in obesity patients at high risk of HF are disputed. The profile of proinflammatory and anti-inflammatory adipocytokines as promising biomarker for HF risk stratification is discussed in the review.

Proteoglycans in Obesity-Associated Metabolic Dysfunction and Meta-Inflammation

Proteoglycans are a specific subset of glycoproteins found at the cell surface and in the extracellular matrix, where they interact with a plethora of proteins involved in metabolic homeostasis and meta-inflammation. Over the last decade, new insights have emerged on the mechanism and biological significance of these interactions in the context of diet-induced disorders such as obesity and type-2 diabetes. Complications of energy metabolism drive most diet-induced metabolic disorders, which results in low-grade chronic inflammation, thereby affecting proper function of many vital organs involved in energy homeostasis, such as the brain, liver, kidney, heart and adipose tissue. Here, we discuss how heparan, chondroitin and keratan sulfate proteoglycans modulate obesity-induced metabolic dysfunction and low-grade inflammation that impact the initiation and progression of obesity-associated morbidities.

ADAMTS1 and HSPG2 mRNA levels in cumulus cells are related to human oocyte quality and controlled ovarian hyperstimulation outcomes

PURPOSE

The study investigated potential correlations between the expression levels of ADAMTS1 and HSPG2 in cumulus cells (CCs) and controlled ovarian hyperstimulation (COH) outcomes.

METHODS

RT-PCR was used to determine ADAMTS1 and HSPG2 mRNA levels in mice CCs at different timepoints (0, 4, 8, 12, and 16 h) after human chorionic gonadotropin (hCG) injection, and in CCs after RNAi treatment. Women with polycystic ovary syndrome (PCOS) (n = 45) and normal ovulatory controls (n = 103) undergoing IVF/ICSI were recruited. Relative ADAMTS1 and HSPG2 mRNA levels were measured by RT-PCR. Moreover, correlations of ADAMTS1 and HSPG2 levels with COH outcomes were analyzed.

RESULTS

At different timepoints after hCG treatment, ADAMTS1 mRNA had the highest level at 12 h, whereas HSPG2 showed opposite profiles to ADAMTS1 with the lowest level at 12 h. HSPG2 expression was upregulated after ADAMTS1 RNAi treatment The PCOS group had higher HSPG2 and lower ADAMTS1 expression levels than controls. In normal ovulatory women (control group), a higher expression of ADAMTS1 and lower expression of HSPG2 were associated with more mature oocytes, transplantable embryos, and good quality embryos, whereas higher transplantable embryo rates and good quality embryo rates were obtained only with lower HSPG2 expression. ROC curves showed the co-measurement of ADAMTS1 and HSPG2 had a better predictive power than separate analyses.

CONCLUSION

The dynamic profiles of ADAMTS1 and HSPG2 were inversely correlated in CCs. In PCOS and normal ovulatory patients, higher ADAMTS1 and lower HSPG2 expression levels in CCs were related to better COH outcomes.

Serum glypican 4 level in obese children and its relation to degree of obesity

OBJECTIVE

Previous adult studies have demonstrated associations of serum glypican 4 (Gpc4) and obesity parameters and insulin sensitivity. However, an association of serum Gpc4 and glucose metabolism remains contradictory. Study of serum Gpc4 in obese children has not been conducted. We aimed to determine serum Gpc4 levels in obese children with various degrees of obesity.

DESIGN, PATIENTS AND MEASUREMENTS

Up to 370 overweight and obese children, aged 6-18 years were enrolled in this cross-sectional study. Oral glucose tolerance test (OGTT) was performed with fasting serum Gpc4, lipid profiles, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) measured. Insulin sensitivity and β-cell function indices were calculated from plasma glucose and serum insulin levels derived from the OGTT. Bioelectrical impedance analysis was performed for body fat determination. Comparisons of serum Gpc4 levels among the groups of children with various degrees of obesity were performed.

RESULTS

Serum Gpc4 levels progressively increased in children with increasing body mass index standard deviation score (BMI SDS) tertiles [median (interquartile range, IQR): 2.3 (1.8, 3.2), 2.6 (1.9, 3.4) and 3.2 (2.4, 3.8) μg/L, P<.001]. There were no differences in serum Gpc4 levels among children in the different glucose metabolism categories. Log serum Gpc4 levels were positively correlated with SDSs of weight and BMI, cholesterol, AST and ALT. No associations of log serum Gpc4 and insulin sensitivity and β-cell function indices were demonstrated.

CONCLUSIONS

Serum Gpc4 levels were increased with increasing degrees of obesity. There were no differences in serum Gpc4 levels among glucose metabolism categories.