Serum visfatin concentrations in gestational diabetes mellitus and normal pregnancy

Biochemical and molecular biomarkers: unraveling their role in gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is the most prevalent metabolic disorder during pregnancy, causing short- and long-term complications for both mother and baby. GDM is a multifactorial disease, and it may be affected by interactions between genetic, epigenetic, and environmental factors. However, the exact etiology is poorly understood. Despite the high prevalence of GDM, there is still debate regarding the optimal time for screening, the diagnostic threshold to apply, and the best strategies for treatment. Identifying effective strategies for therapeutic purposes as well as accurate biomarkers for prognostic and diagnostic purposes will reduce the GDM incidence and improve its management. In recent years, new biochemical and molecular biomarkers such as microRNAs, single-nucleotide polymorphisms, and DNA methylation have received great interest in the diagnosis of GDM. In this review, we discuss current and future diagnostic approaches for the detection of GDM and evaluate lifestyle and pharmacological strategies for GDM prevention.

Analysis and Prediction of Gestational Diabetes Mellitus by the Ensemble Learning Method

Gestational diabetes mellitus (GDM) is the most common disease in pregnancy and can cause a series of maternal and infant complications. A new study shows that GDM affects one in six deliveries. Identifying and screening for risk factors for GDM can effectively help intervene and improve the condition of women and their children. Therefore, the aim of this paper is to determine the risk factors for GDM and to use the ensemble learning method to judge whether pregnant women suffer from GDM more accurately. First, this study involves six commonly used machine learning algorithms to analyze the GDM data from the Tianchi competition, selects the risk factors according to the ranking of each model, and uses the Shapley additive interpreter method to determine the importance of the selected risk factors. Second, the combined weighting method was used to analyze and evaluate the risk factors for gestational diabetes and to determine a group of important factors. Lastly, a new integrated light gradient-boosting machine-extreme gradient boosting-gradient boosting tree (LightGBM-Xgboost-GB) learning method is proposed to determine whether pregnant women have gestational diabetes mellitus. We used the gray correlation degree to calculate the weight and used a genetic algorithm for optimization. In terms of prediction accuracy and comprehensive effects, the final model is better than the commonly used machine learning model. The ensemble learning model is comprehensive and flexible and can be used to determine whether pregnant women suffer from GDM. In addition to disease prediction, the model can also be extended for use to many other areas of research.

Measuring visfatin levels in saliva: an alternative approach to gestational diabetes screening

Objective

Oral glucose tolerance testing (OGTT) is the current recommended approach for the diagnosis of gestational diabetes mellitus (GDM). Visfatin is a type of novel adipokine of interest that mostly participates in glucose metabolism and inflammatory processes. We aim to identify a screening technique for GDM using salivary visfatin levels and to establish this technique's value as a screening method compared to OGTT.

Methods

This is a cross-sectional case-control study. The cohort was formed from the saliva samples of pregnant patients in their 24^th through 28^th weeks of gestation. Patients were divided into two groups depending on their GDM status. OGTT and visfatin test results were compared and subjected to further analysis to establish a cutoff value for visfatin testing.

Results

ELISA results indicated a significant difference between patients with GDM compared to patients without GDM; the values were 18.89 ± 9.59 and 12.44 ± 8.75, respectively (p: 0.007). A cutoff value of 10.5 ng/mL can be used to detect GDM with 78% sensitivity and 51% specificity.

Conclusion

Salivary visfatin levels were significantly higher in patients with GDM. The existence of a differential in the concentration of visfatin in saliva can be utilized to develop a new screening method for GDM.

Visfatin level and gestational diabetes mellitus: a systematic review and meta-analysis

It is reported that elevated visfatin level is associated with gestational diabetes mellitus (GDM). However, the relationship between visfatin level and GDM remains controversial. The aim of our study was to systematically review available literature linking visfatin to GDM for a comprehensive understanding of the relationship between circulating visfatin level and GDM in human. PubMed, The Cochrane Library and Web of Science were searched for studies published up to July 2020. Standard mean difference with 95% confidence interval was calculated to evaluate the relationship between visfatin level and GDM using the Review Manager 5.3 and Stata 12.0. The evidence indicated that no significant difference was observed in the level of circulating visfatin between the women with GDM and normal glucose tolerance, suggesting circulating visfatin level is not independently related to GDM. Nevertheless, visfatin is involved in the development of GDM in obese women.

The relation of visfatin with nausea and vomiting in the pregnancy

Background

The etiology of nausea and vomiting during pregnancy (NVP) is unclear and appears multifactorial. It has been shown that the physiological changes associated with NVP include changes in the levels of adipocytokines. Therefore, we investigated the association of nausea and vomiting during pregnancy with visfatin, β-human chorionic gonadotropin (βHCG), and perceived stress.

Materials and Methods

In this cross-sectional study, 100 nulliparous pregnant women aged 18-45 years were evaluated. Participants completed two questionnaires including the Index of Nausea, Vomiting, and Retching (INVR) and Perceived Stress Scale (PSS) in the three trimesters of pregnancy. They also referred to the laboratory to conduct the biochemical examinations including serum visfatin and βHCG levels in three trimesters. The obtained data were analyzed by SPSS 16 using statistical repeated-measures analysis of variance, Friedman, Bonferroni, and Wilcoxon post hoc tests. Marginal model (method generalized estimating equation [GEE]) was performed to assess the predictors of the INVR in the participants.

Results

INVR, PSS, visfatin, and βHCG levels significantly decreased from the first trimester to the third trimester of pregnancy (P ≤ 0.001). As a result of simple marginal model (GEE method), visfatin was predicted log βHCG (P = 0.035). Furthermore, the multiple marginal model revealed that the two predictors of βHCG (P = 0.01) and PSS (P ≤ 0.001) were positively correlated with the INVR. Furthermore, visfatin had an indirect positive effect on INVR.

Conclusion

The present study showed that visfatin can be indirectly related with nausea and vomiting throughout pregnancy. Furthermore, it seems that fluctuations in visfatin levels are independent of weight gain during pregnancy.

Predictive and diagnostic biomarkers for gestational diabetes and its associated metabolic and cardiovascular diseases

Gestational diabetes mellitus (GDM) is defined as the presence of high blood glucose levels with the onset, or detected for the first time during pregnancy, as a result of increased insulin resistance. GDM may be induced by dysregulation of pancreatic β-cell function and/or by alteration of secreted gestational hormones and peptides related with glucose homeostasis. It may affect one out of five pregnancies, leading to perinatal morbidity and adverse neonatal outcomes, and high risk of chronic metabolic and cardiovascular injuries in both mother and offspring. Currently, GDM diagnosis is based on evaluation of glucose homeostasis at late stages of pregnancy, but increased age and body-weight, and familiar or previous occurrence of GDM, may conditionate this criteria. In addition, an earlier and more specific detection of GDM with associated metabolic and cardiovascular risk could improve GDM development and outcomes. In this sense, 1st-2nd trimester-released biomarkers found in maternal plasma including adipose tissue-derived factors such as adiponectin, visfatin, omentin-1, fatty acid-binding protein-4 and retinol binding-protein-4 have shown correlations with GDM development. Moreover, placenta-related factors such as sex hormone-binding globulin, afamin, fetuin-A, fibroblast growth factors-21/23, ficolin-3 and follistatin, or specific micro-RNAs may participate in GDM progression and be useful for its recognition. Finally, urine-excreted metabolites such as those related with serotonin system, non-polar amino-acids and ketone bodies, may complete a predictive or early-diagnostic panel of biomarkers for GDM.

Circulating visfatin levels in the second and third trimester of pregnancies with gestational diabetes: a systematic review

INTRODUCTION

There are multiple published conflicting associations of the adipocytokine visfatin with gestational diabetes. In this study, we attempted to investigate this relationship via a systematic review of the published literature.

EVIDENCE ACQUISITION

Literature retrieval using PubMed, Google Scholar, Scopus and Hydi databases followed by article selection and data extraction were conducted. Relevant studies published up to June 2018 were included. In total, 29 cohorts that were published in 27 articles were analyzed. Three studies carried out in early pregnancy were excluded. A total of 2365 individuals, with 1069 gestational diabetes (GDM) cases and 1296 controls from studies describing visfatin in the second or third trimester of gestation were included.

EVIDENCE SYNTHESIS

The difference in visfatin levels between women with GDM and the controls in the second and third trimester was measured by weighted mean difference (WMD) and 95% confidence intervals (CI). Heterogeneity was inspected by using both subgroup and meta-regression analysis. Analysis was restricted to studies describing singleton pregnancies. The quality of included studies was assessed by the Newcastle-Ottawa Scale.

CONCLUSIONS

No significant difference in circulating visfatin levels in GDM during the second trimester of pregnancy (WMD -0.30 ng/mL, 95% CI: -2.06, 1.45, SE=0.895, P=0.733) was detected. Meta-analysis of the studies in the third trimester revealed a significant negative effect, that was however driven by only one study. This finding limits the meaningful interpretation of the pooled analysis. Significant heterogeneity was identified between studies, and meta-regression analysis showed that homeostatic model assessment for insulin resistance contributes significantly to heterogeneity. In conclusion, our findings suggest that peripheral blood visfatin concentration cannot be robustly associated with gestational diabetes status in the second and third trimesters of pregnancy.

Serum levels of adipokines in gestational diabetes: a systematic review

OBJECTIVE

To determine the difference of serum levels of 10 adipokines (apelin, chemerin, fatty acid-binding protein-4, fibroblast growth factor-21, monocyte chemoattractant protein-1, nesfatin-1, omentin-1, resistin, vaspin, and visfatin) among women with gestational diabetes and healthy pregnant controls.

MATERIALS AND METHODS

Literature search was conducted using the Medline (1966-2018), Scopus (2004-2018), Cochrane Central Register of Controlled Trials (CENTRAL) (1999-2018), Clinicaltrials.gov (2008-2018) and Google Scholar (2004-2018) databases, along with the reference list of the included studies.

RESULTS

Ninety-one studies were included in the present review, with a total number of 11,074 pregnant women. A meta-analysis was not conducted due to the high inter-study heterogeneity. Current evidence suggests that fatty acid-binding protein-4 levels are significantly increased in pregnancies complicated with gestational diabetes, while no association of serum apelin and monocyte chemoattractant protein-1 with the disease can be supported. Data regarding the rest adipokines are conflicting, since the available studies did not unanimously indicate a significant change of their levels in gestational diabetes.

CONCLUSIONS

The findings of the present systematic review suggest the promising role of fatty acid-binding protein-4 in the prediction of gestational diabetes, while inconsistent evidence exists regarding the rest novel adipokines. Future cohorts are needed to assess their predictive efficacy and fully elucidate their contribution in the disease.

Adipokine levels in overweight women with early-onset gestational diabetes mellitus

PURPOSE

The study of adipokines in overweight women with early-onset (diagnosed before 20 weeks) gestational diabetes mellitus (GDM) could help to understand the ethiopathological mechanisms of this disorder. Our aim was to assess adipokine levels in overweight pregnant women with early-onset GDM compared to patients with standard-onset (diagnosed at 24-28 weeks) GDM and to glucose-tolerant women at the same gestational ages.

METHODS

This nested case-control study included 133 overweight pregnant women: 33 with early-onset (diagnosed < 20 weeks) GDM; 40 with standard-onset (diagnosed ≥ 24 weeks) GDM and 60 glucose-tolerant (normal oral glucose tolerance tests < 20 and ≥ 24 weeks). Adiponectin, leptin, resistin, visfatin and ghrelin serum levels were measured by ELISA.

RESULTS

Adiponectin serum levels were significantly lower in early-onset GDM women than in standard-onset GDM patients or controls matched for gestational age. Leptin serum levels were significantly higher in women with early-onset GDM than in controls. Women with early-onset GDM had lower adiponectin/leptin ratio than those with standard-onset GDM. There were no significant differences in resistin, ghrelin and visfatin serum levels among the participants.

CONCLUSIONS

Our results suggest that, compared to overweight glucose-tolerant women and patients with standard-onset GDM, overweight women with early-onset GDM have unbalanced adipokine levels, suggesting that they have a more inflammatory profile.

Association between serum visfatin levels and atherosclerotic plaque in patients with type 2 diabetes

BACKGROUND

Visfatin is a multifaceted protein that plays an important role in regulating a variety of physiological and pathological processes, including obesity, diabetes and cardiovascular disease. However, circulating visfatin levels in atherosclerosis plaque progression in patients with type 2 diabetes, or its association with the vascular territory affected remain unclear.

METHODS

We evaluated the relationship between visfatin levels and carotid or femoral artery atherosclerosis in Chinese patients with type 2 diabetes. Serum levels of visfatin were measured by enzyme-linked immunosorbent assay (ELISA) in 97 inpatients with type 2 diabetes. Carotid and/or femoral atherosclerotic plaques were detected by B-mode ultrasound.

RESULTS

Serum visfatin levels were elevated in the group with atherosclerotic plaques compared to the control group without plaques [0.68 (0.46-1.58) versus 0.45 (0.23-0.76) ng/mL, respectively, P = 0.0002]. Patients with carotid plaques showed higher visfatin levels than those with or without femoral plaques. Pearson's correlation analysis showed that serum visfatin levels were positively correlated with waist circumference (r = 0.226, P = 0.029), waist-hip ratio (r = 0.221, P = 0.032), TG (r = 0.222, P = 0.030) and number of plaques (r = 0.275, P = 0.009). Logistic regression analysis showed that a higher serum visfatin level was an independent predictor for the presence of atherosclerotic plaques.

CONCLUSIONS

In conclusion, among patients with T2DM, serum visfatin levels were elevated in those with atherosclerotic plaques, especially in patients with carotid atherosclerotic plaques. Serum visfatin may serve as a predictor of atherosclerotic plaques in patients with T2DM.

Association between circulating visfatin and gestational diabetes mellitus: a systematic review and meta-analysis

AIMS

Gestational diabetes mellitus (GDM) is a medical complication of any degree of glucose intolerance with onset or first recognition during pregnancy. Although visfatin is commonly considered to be related to GDM, studies revealed inconsistent results. This study aimed to clarify the relationship between visfatin and GDM.

METHODS

The protocol for this study was registered in PROSPERO (No. CRD42018086204) in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). PubMed and Embase databases were used to search for relevant studies published up to September 30, 2017. The difference of visfatin levels between women with GDM and the controls was measured by standardised mean difference (SMD) and 95% confidence interval (CI).

RESULTS

Twenty-six studies that were published in 24 articles met the inclusion criteria, in which 2305 participants (1033 with GDM, mean age 31.39 years and 1272 controls, and mean age 29.99 years) were included. The quantitative meta-analysis revealed no significant difference in circulating visfatin levels between women with GDM and the controls (SMD = 0.249, 95% CI = - 0.079 to 0.576, P = 0.137). Subgroup analyses were performed referring to body mass index (BMI) where inconsistent results have been observed between cases and controls groups. For the ten studies, in which the level of BMI in women with GDM was higher than that in the control group, the pooled result showed that circulating visfatin was significantly higher among women with GDM than the controls (SMD = 0.367, 95% CI = 0.06 to 0.728, P = 0.046). Of other 16 studies BMI-matched, the pooled SMD illustrated no difference of visfatin.

CONCLUSIONS

Our study elucidates that visfatin is not independently associated with GDM. Visfatin is linked to GDM through maternal overweight/obesity, which is one of the major factors leading to the development of GDM.

The association between adipocytokines and glycemic control in women with gestational diabetes mellitus

Objective: To evaluate the relationship between adipocytokines and glycemic control.Study design: Prospective observational trial of gestations with gestational diabetes mellitus (GDM). Fasting glucose (FG), insulin, adiponectin, leptin, chemerin, retinol-binding protein 4 (RBP-4), osteocalcin, and resistin were measured. HomeOstasis model assessment of insulin resistance (HOMA-IR) and QUantitative insulin sensitivity ChecK Index (QUICKI) were calculated. Women who required medications for glycemic control were compared to women using nutritional therapy only.Results: Overall, 75 women were included -26 (34.7%) required medications to achieve good glycemic control. Factors associated with poor control are as follows: low resistin (aOR 0.84), HOMA-IR (aOR 1.96), QUICKI (aOR 0.62), first trimester FG (aOR 1.43), and maternal age (aOR 1.26). HOMA-IR and QUICKI performed highest for prediction. Resistin, first trimester FG, maternal age, and QUICKI had an AUC of 0.878, sensitivity and specificity of 87.5% for the prediction of the need for medications.Conclusions: Low resistin is associated with poor control. A model utilizing maternal age, first trimester fasting glucose, and first visit QUICKI yields good predictability.

Circulating adipokines and mRNA expression in adipose tissue and the placenta in women with gestational diabetes mellitus

Maternal adipose tissue and the placenta secrete various molecules commonly called adipokines such as chemerin, omentin-1, visfatin, adiponectin, and leptin that are important players in the pathogenesis of insulin resistance. Gestational diabetes mellitus (GDM) is defined as a state of glucose intolerance characterized by β-cell dysfunction and insulin resistance. To examine whether circulating adipokines and their mRNA expression in the adipose tissue and the placenta are altered in GDM pregnancy, we compared 15 GDM women [obese (BMI > 30) and non-obese (BMI < 30)] to 23 NGT (normal glucose tolerance) women [obese and non-obese], at the time of the Cesarean section. Circulating chemerin and leptin were higher (p = 0.009 and p = 0.005, respectively) and circulating omentin-1, visfatin, as well as the adiponectin/leptin ratio were lower (p = 0.039, p = 0.007 and p = 0.011, respectively) in GDM-obese compared to NGT-non-obese women. Chemerin and leptin correlated positively with BMI and HOMA-IR and omentin-1 correlated negatively with BMI. Serum TNF-α was significantly elevated in all obese compared to non-obese pregnant women and correlated positively with BMI. Adiponectin levels were reduced -although not significantly- in GDM- and NGT-obese women compared to their non-obese counterparts. Resistin, RPB4 and IL-6 levels did not differ significantly between groups. Chemerin mRNA expression in subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) was significantly higher compared to placenta in all women (6-to 24-times, p < 0.05). Chemerin-VAT mRNA expression in GDM-obese tended to be significantly higher compared to NGT-non-obese women (3-times, p = 0.005). Omentin-1 mRNA expression was significantly higher in VAT compared to SAT (50- to 100-times, p < 0.01) and its expression in placenta was negligible in all women. Although, leptin was expressed significantly higher in SAT compared to VAT and the placenta in all women (5- to 46-times, p < 0.05), only its mRNA expression in VAT of obese (GDM and NGT) differed significantly when compared to NGT-non-obese women (3-times higher, p < 0.02). Visfatin mRNA expression was comparable in all tissues. In conclusion, chemerin and leptin are elevated and omentin-1 and visfatin levels are decreased in GDM women complicated by obesity. This finding together with the positive association of chemerin and leptin with markers of insulin resistance, suggests that these adipokines and more especially chemerin and leptin accompanied by their adipose tissue expression could contribute to the increased insulin resistance and low grade inflammation that characterizes GDM-obese women.

Genetic associations of the visfatin G-948T polymorphism with obesity-related metabolic traits in an Iranian population

Background:

Obesity is a global public health problem. Visfatin, as an adipocytokine, is coded by a gene known as nicotinamide phosphoribosyltransferase. So far, results were conflicted regarding correlations of visfatin with obesity and metabolic variables. The present study aimed to explore the association between G-948T polymorphism of visfatin gene with obesity and lipid profile in a nationally representative sample of Iranian population.

Materials and Methods:

In this case–control study, we assessed 129 randomly selected patients with obesity and 182 healthy normal weight controls from participants of Isfahan Healthy Heart Program. Genomic DNA was isolated from peripheral blood cells, and high-resolution melt polymerase chain reaction was performed to explore the presence of G-948T polymorphism.

Results:

T carriers “GT + TT” were statistically more frequent in the obese patients than the controls (P = 0.013; odds ratio = 1.9, 95% confidence interval = 1.1–3.1). The serum levels of total cholesterol and low-density lipoprotein cholesterol (LDL-C) were significantly different between T carriers and GG homozygote genotype (P = 0.03 and 0.02, respectively).

Conclusion:

We concluded that visfatin G-948T polymorphism was correlated with obesity, total cholesterol, and LDL-C levels in our population.

Are adipokines associated with gestational diabetes mellitus?

OBJECTIVE

To investigate the association of maternal serum levels of chemerin, retinol binding protein-4 (RBP-4), and visfatin with gestational diabetes mellitus (GDM).

MATERIAL AND METHODS

158 pregnant women were screened between 24 and 28 weeks of gestation. They were divided into two groups: GDM group (n=76) and control group (n=82). Maternal serum concentrations of chemerin, RBP-4, visfatin, insulin, and homeostasis model assessment-insulin resistance (HOMA-IR) were assessed.

RESULTS

There were no differences in age and gestational age between the GDM group and the control group (p=0.058 and p=0.820, respectively). Body mass index (BMI) at 24 to 28 weeks of gestation was higher in the GDM group (p<0.001). The serum concentrations of RBP-4, chemerin, and visfatin did not demonstrate significant differences between the GDM and control groups (p=0.871, p=0.100, and p=0.886, respectively). Significant differences in serum level of insulin and HOMA-IR were found between the GDM and control groups (14.94 vs 9.87, p<0.001 and 3.73 vs 1.77, p<0.001, respectively). Correlation analyses of chemerin, RBP-4, visfatin, insulin, and HOMA-IR in both groups revealed a weak degree of positive correlation between RBP-4 and chemerin (Spearman r=0.251, p=0.026) and a strong positive correlation between maternal insulin and HOMA (Spearman r=0.868, p<0.001).

CONCLUSION

No differences were found in serum chemerin, RBP-4, and visfatin between pregnant women with GDM and healthy pregnant women. Further prospective studies will be essential to elucidate the contribution of adipokines to GDM and the positive correlation between maternal RBP-4 and chemerin.

The Role of Energy, Nutrients, Foods, and Dietary Patterns in the Development of Gestational Diabetes Mellitus: A Systematic Review of Observational Studies

OBJECTIVE

Diet may influence the risk of gestational diabetes mellitus (GDM), but inconsistent findings have been reported. The purpose of this study was to synthesize evidence from observational studies on the associations between dietary factors and GDM.

RESEARCH DESIGN AND METHODS

Medline and Embase were searched for articles published until January 2015. We included observational studies of reproductive-aged women that reported on associations of maternal dietary intake before or during pregnancy, including energy, nutrients, foods, and dietary patterns, with GDM. All relevant results were extracted from each article. The number of comparable studies that adjusted for confounders was insufficient to perform a meta-analysis.

RESULTS

The systematic review included 34 articles comprising 21 individual studies (10 prospective cohort, 6 cross-sectional, and 5 case-control). A limited number of prospective cohort studies adjusting for confounders indicated associations with a higher risk of GDM for replacing 1-5% of energy from carbohydrates with fat and for high consumption of cholesterol (≥300 mg/day), heme iron (≥1.1 mg/day), red and processed meat (increment of 1 serving/day), and eggs (≥7 per week). A dietary pattern rich in fruit, vegetables, whole grains, and fish and low in red and processed meat, refined grains, and high-fat dairy was found to be beneficial. The current evidence is based on a limited number of studies that are heterogeneous in design, exposure, and outcome measures.

CONCLUSIONS

The findings support current dietary guidelines to limit consumption of foods containing saturated fat and cholesterol, such as processed meat and eggs, as part of an overall balanced diet. Further large prospective studies are warranted.

The endocrine function of human placenta: an overview

During pregnancy, several tightly coordinated and regulated processes take place to enable proper fetal development and gestational success. The formation and development of the placenta is one of these critical pregnancy events. This organ plays essential roles during gestation, including fetal nourishment, support and protection, gas exchange and production of several hormones and other mediators. Placental hormones are mainly secreted by the syncytiotrophoblast, in a highly and tightly regulated way. These hormones are important for pregnancy establishment and maintenance, exerting autocrine and paracrine effects that regulate decidualization, placental development, angiogenesis, endometrial receptivity, embryo implantation, immunotolerance and fetal development. In addition, because they are released into maternal circulation, the profile of their blood levels throughout pregnancy has been the target of intense research towards finding potential robust and reliable biomarkers to predict and diagnose pregnancy-associated complications. In fact, altered levels of these hormones have been associated with some pathologies, such as chromosomal anomalies or pre-eclampsia. This review proposes to revise and update the main pregnancy-related hormones, addressing their major characteristics, molecular targets, function throughout pregnancy, regulators of their expression and their potential clinical interest.

The role of visfatin (PBEF/Nampt) in pregnancy complications

Visfatin (PBEF/Nampt) is an adipocytokine that exerts pleiotropic effects within the human body, particularly affecting its metabolism and immunity. Visfatin was originally identified as being secreted by peripheral blood lymphocytes acting as a pre-B-cell colony-enhancing factor (PBEF). However, it was subsequently reported to be expressed in almost every tissue of the human body, with visceral fat deposits being the main source of visfatin. In addition to its secreted form, visfatin may also be found intracellularly where it functions as a nicotinamide phosphoribosyltransferase (Nampt). Visfatin maternal plasma concentrations increase during pregnancy, suggesting its important role in this complicated process. Alterations in visfatin level also take place in patients during pregnancy complications. This review focuses on the ones that most commonly occur in connection with visfatin: preterm labor, pre-eclampsia and gestational diabetes mellitus. The review aims to provide a better understanding of the role of visfatin during pregnancy and the causes of its alteration in maternal plasma, highlighting the potential use of visfatin as a diagnostic marker of pregnancy complications in the future.

Relationship of maternal serum resistin and visfatin levels with gestational diabetes mellitus

INTRODUCTION

Adiponectin, resistin and visfatin are thought to play role in the pathophysiology of gestational diabetes (GDM). In this study, we aimed to investigate the association of maternal second trimester serum resistin and visfatin levels with GDM.

MATERIALS AND METHODS

Screening and diagnosis for GDM was performed between the 24-28th gestational weeks. About 40 women diagnosed with GDM and 40 non-diabetic women constituted the study and control groups, respectively. Groups were compared for second trimester maternal serum resistin, visfatin and HbA1c levels, HOMA-IR and postpartum 75 g OGTT results.

RESULTS

Mean serum resistin (p = 0.071) and visfatin (p = 0.194) levels were similar between the groups. However, mean BMI (p = 0.013), HOMA-IR (p = 0.019), HbA1c (p < 0.0001) and birth weight (p = 0.037) were significantly higher in GDM group compared to controls. Type 2 diabetes and impaired glucose tolerance were detected in 2 (5%) and 7 (20%) women in the GDM group, respectively, with 75 g OGTT performed at the postpartum 6th week. Resistin levels of patients with GDM and postpartum glucose intolerance were higher than those with GDM but no postpartum glucose intolerance (p = 0.012). Visfatin levels in the GDM group showed a positive correlation with biparietal diameter, head circumference, abdominal circumference and femur length (p < 0.05).

CONCLUSION

Maternal serum resistin and visfatin levels are unchanged in GDM. In patients with GDM, second trimester resistin levels may be predictive for postpartum glucose intolerance and second trimester visfatin levels may be related with fetal biometric measurements. Further larger studies are needed.

Management of reproduction and pregnancy complications in maternal obesity: which role for dietary polyphenols?

Obesity is a global and dramatic public health problem; maternal obesity represents one of the main risk factors of infertility and pregnancy complications as it is associated with adverse maternal and offspring outcomes. In the last few years, adipose tissue dysfunction associated with altered adipocytokine secretion has been suggested to play a critical role in all the phases of reproductive process. Obesity is a nutrition-related disorder. In this regard, dietary intervention strategies, such as high intake of fruit and vegetables, have shown significant effects in both preserving health and counteracting obesity-associated diseases. Evidence has been provided that polyphenols, important constituents of plant-derived food, can influence developmental program of oocyte and embryo, as well as pregnancy progression by modulating several cellular pathways. This review will examine the controversial results so far obtained on adipocytokine involvement in fertility impairment and pregnancy complications. Furthermore, the different effects exerted by polyphenols on oocyte, embryo, and pregnancy development will be also taken in account.

Central visfatin potentiates glucose-stimulated insulin secretion and β-cell mass without increasing serum visfatin levels in diabetic rats

INTRODUCTION

Our previous study revealed that plasma visfatin levels were lower in pregnant women with gestational diabetes (GDM) than non-GDM independent of prepreganacy BMI. We examined whether central visfatin modulates energy and glucose homeostasis via altering insulin resistance, insulin secretion or islet morphometry in diabetic rats.

METHODS

Partial pancreatectomized, type 2 diabetic, rats were interacerbroventricularly infused with visfatin (100ng/rat/day, Px-VIS), visfatin+visfatin antagonist, CHS-828 (100μg/rat/day, Px-VIS-ANT), or saline (control, Px-Saline) via osmotic pump, respectively, for 4weeks.

RESULTS

Central visfatin improved insulin signaling (pAkt→pFOXO-1) but not pSTAT3 in the hypothalamus. Central visfatin did not alter serum visfatin levels in diabetic rats whereas the levels were higher in non-diabetic rats than diabetic rats. Body weight at the 2nd week was lowered in the Px-VIS group due to decreased food intake in the first two weeks compared to the Px-Saline group and energy expenditure was not significantly different among the treatment groups of diabetic rats. Visfatin antagonist treatment nullified the central visfatin effect. Px-VIS increased whole body glucose disposal rates in euglycemic hyperinsulinemic clamp compared to Px-Saline and lowered hepatic glucose output, whereas Px-VIS-ANT blocked the visfatin effect on insulin resistance (P<0.05). In hyperglycemic clamp study, the area under the curve of insulin in first and second phase were significantly higher in the Px-VIS group than the Px-Saline group without modifying insulin sensitivity at the hyperglycemic state, whereas the increase in serum insulin levels was blocked in the Px-VIS-ANT group. Central visfatin also increased β-cell mass by increasing β-cell proliferation.

CONCLUSIONS

Central visfatin improved glucose homeostasis by increasing insulin secretion and insulin sensitivity at euglycemia through the hypothalamus in diabetic rats. Therefore, visfatin is a positive modulator of glucose homeostasis by delivering the hypothalamic signals into the peripheries.

Portal and systemic levels of visfatin in morbidly obese subjects undergoing bariatric surgery

The aim of the present study was to compare the levels of visfatin in portal and systemic circulations and to assess the possible relationship of visfatin with systemic inflammation and insulin resistance in morbidly obese patients undergoing bariatric surgery. A total of 46 morbidly obese patients (BMI = 45.3 ± 5.3 kg/m(2)) undergoing bariatric surgery were included in this study. Blood samplings were performed simultaneously from portal and systemic veins during surgery. Visfatin was measured in both portal and systemic venous samples. Besides, fasting serum levels of insulin, glucose, lipid profile, visfatin, and hs-CRP were determined in systemic venous blood samples. Insulin sensitivity was estimated using the homeostasis model assessment of insulin resistance (HOMA-IR). Visfatin concentrations were significantly higher in portal vein than systemic veins (11.9 ± 12.1 vs. 5.1 ± 3.3 ng/ml, p < 0.0001). While systemic levels of visfatin were significantly correlated with circulating levels of hs-CRP (r = 0.527, p < 0.0001), there were no significant correlations between portal levels of visfatin with systemic levels of hs-CRP concentrations. Substantially higher levels of visfatin in portal vein than systemic veins provide evidence that visceral adipose tissue is the major secretory source of visfatin in humans. Our findings underscore that visceral adipose tissue is an active endocrine organ that is involved in the complex interrelationship between obesity and pathologic conditions.