Maternal leptin, adiponectin, resistin, visfatin and tumor necrosis factor-alpha in normal and gestational diabetes

Adipokines in pregnancy

Reproductive success consists of a sequential events chronology, starting with the ovum fertilization, implantation of the embryo, placentation, and cellular processes like proliferation, apoptosis, angiogenesis, endocrinology, or metabolic changes, which taken together finally conduct the birth of healthy offspring. Currently, many factors are known that affect the regulation and proper maintenance of pregnancy in humans, domestic animals, or rodents. Among the determinants of reproductive success should be distinguished: the maternal microenvironment, genes, and proteins as well as numerous pregnancy hormones that regulate the most important processes and ensure organism homeostasis. It is well known that white adipose tissue, as the largest endocrine gland in our body, participates in the synthesis and secretion of numerous hormones belonging to the adipokine family, which also may regulate the course of pregnancy. Unfortunately, overweight and obesity lead to the expansion of adipose tissue in the body, and its excess in both women and animals contributes to changes in the synthesis and release of adipokines, which in turn translates into dramatic changes during pregnancy, including those taking place in the organ that is crucial for the proper progress of pregnancy, i.e. the placenta. In this chapter, we are summarizing the current knowledge about levels of adipokines and their role in the placenta, taking into account the physiological and pathological conditions of pregnancy, e.g. gestational diabetes mellitus, preeclampsia, or intrauterine growth restriction in humans, domestic animals, and rodents.

Endostatin and Cystatin C as Potential Biomarkers for Early Prediction of Preeclampsia

Preeclampsia (PE) is characterized by new onset hypertension and proteinuria. Undoubtedly, some individuals do not fit precisely into this description, and it could be challenging to spot newly developed PE in females who already have hypertension or renal illness. Monitoring the disease's progression enables the optimization of delivery time while minimizing premature births. The current study explores the diagnostic benefits of serum endostatin and cystatin C in addition to serum and urinary magnesium (Mg) and fractional excretion magnesium (FEMg) for early prediction of PE. The population sample included 82 pregnant women divided into 3 groups: normal pregnancy group served as a control (n = 26), nonpreeclampsia (NPE, n = 34) group included pregnant women with one or more risk factors but did not progress to PE, and pregnant women who developed preeclampsia (PE, n = 22) group. Blood samples were withdrawn at two sampling times: at 12th to 16th and 24th to 26th weeks of gestation. Compared to normal pregnancy, results (X̅ ± SD) indicated a significant increase in serum endostatin in NPE at the first sample (10.78 ± 3.63 ng/mL) and the second sample (28.03 ± 3.79 ng/mL), while cystatin C was at the first sample (0.68 ± 0.06 mg/dL) and the second sample (0.71 ± 0.07 mg/dL). In the PE group, the serum endostatin was 18.86 ± 4.37 ng/mL at the first sampling time and 53.56 ± 9.76 ng/mL for the second sample. Serum cystatin C was also elevated in PE with X̅ ± SD equivalent to 0.73 ± 0.08 and 0.89 ± 0.08 mg/dL at the first and second samples, respectively. On the other hand, serum and urinary Mg in addition to FEMg levels did not significantly differ across the groups under study. Receiver operating characteristic (ROC) curve analysis proved that both endostatin and cystatin C could be good indicators for PE. The findings imply that measuring endostatin and cystatin C at early pregnancy and before progression to PE may be effective in detecting the likelihood of PE. Endostatin could be more precise and sensitive in assessing the probability of PE than cystatin C; however, coupling of the two parameters may be promising.

The Effect of Vitamin D3 Intervention on the Association Among Vitamin D3, Adiponectin, and Body Mass Index in Pregnant Women With Gestational Diabetes

INTRODUCTION

Vitamin D3 (VD3) deficiency is a strong predictor of gestational diabetes. Therefore, VD3 supplementation during the antenatal period could prevent the development of gestational diabetes via its effects on insulin secretion, insulin sensitivity, body mass index (BMI), and adiponectin production.

OBJECTIVES

To observe the effect of VD3 supplementation on adiponectin and BMI and to explore the effect of VD3 supplementation on the association among VD3, adiponectin, and BMI in pregnant women with gestational diabetes.

METHODS

A randomized control trial was performed after receiving consent at Postgraduate Medical Institute, Lahore. Subjects at 20-26 weeks of gestation with gestational diabetes and with a deficiency/insufficiency of VD3 were included. The study excluded those who were smokers, had multiple pregnancies, or had other gestational complications. Subjects were categorized into interventional (VD3 supplementation) and control groups. The institutional ethical committee approved the study. Serum samples were used for enzyme-linked immunosorbent assay estimation of VD3 and adiponectin levels. Statistical Product and Service Solutions (SPSS) (IBM SPSS Statistics for Windows, Version 21.0, Armonk, NY) software was used to analyze data. Student t-tests were applied to compare quantitative variables, and Chi-square tests were utilized to compare qualitative variables. Pearson's correlation and linear regressions were performed to explore the association. At a 95% confidence interval, a p-value of ≤0.05 was taken as significant.

RESULTS

With an increase in serum VD3 levels, a decrease in serum adiponectin level was observed in pregnant women with gestational diabetes (interventional group: r = -0.088, p = 0.74); however, after the intervention of VD3 supplementation in the same subjects, an increase in serum adiponectin level was noted with an increase in VD3 (interventional group: r = 0.273, p = 0.28). A significant direct relationship was found between BMI and adiponectin in the same study population (interventional group: r = 0.7, p = 0.001). Interestingly, after the intervention, BMI tends to be less likely to increase adiponectin levels (interventional group: r = 0.09, p = 0.73). Moreover, an inverse association was exhibited between BMI and VD3 levels in all the study groups before intervention (control group: r = -0.07, p = 0.78; interventional group: r = -0.035, p = 0.89) and after intervention (interventional group: r = -0.12, p = 0.65), except in the control group after the intervention span, where BMI mildly raises the VD3 levels (r = -0.12, p = 0.65).

CONCLUSION

BMI increases with an increase in serum adiponectin levels in gestational diabetic women, but after VD3 supplementation, BMI was less likely to influence adiponectin. Also, with an increase in BMI, a decrease in the VD3 in all study groups was observed except in the control group after VD3 supplementation.

Association between serum interleukin-6, leptin and insulin in gestational diabetes mellitus - a cross- sectional study

Purpose

Gestational diabetes mellitus (GDM) is a state of leptin resistance which develops a vicious cycle of hyperinsulinemia and hyperleptinemia leading to aggravation of an inflammatory situation. This study was done to find out the association between IL-6, leptin and insulin in gestational diabetes among North Indian women.

Method

This cross-sectional study included 100 GDM, 100 non-GDM and 50 non-pregnant women. DIPSI (Diabetes in Pregnancy Study Group India) criteria was used for screening GDM among pregnant women. GDM and non-GDM pregnant women were further categorized into three groups according to the trimester of pregnancy. Serum IL-6, leptin and insulin were measured in all the enrolled women.

Results

Serum IL-6 levels were significantly higher among GDM women as compared to non-GDM and non-pregnant women. Although the mean serum leptin and insulin levels were higher in GDM, but the difference was not statistically significant. When GDM and non-GDM women were categorized into three trimester, serum leptin levels were found to be significantly higher in 3rd trimester (p < 0.002) and IL-6 in 1st trimester (p < 0.017) among GDM women. No correlation was found between serum IL-6, leptin and insulin in GDM.

Conclusion

Absence of any significant association between leptin and IL-6 signifies that leptin may not be associated with inflammation in gestational diabetes. However, IL-6 may serve as an early marker for screening glucose intolerance during pregnancy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01188-3.

Influence of Pre-Pregnancy Obesity on Carbohydrate and Lipid Metabolism with Selected Adipokines in the Maternal and Fetal Compartment

A higher body mass index (BMI) before pregnancy is associated with an increased risk of maternal and perinatal complications. This study aimed to analyze selected parameters of carbohydrate and lipid metabolism, including adipokines, in obese pre-pregnant women, and their influence on the birth weight of newborns.

MATERIALS AND METHODS

The study group (O) consisted of 34 pregnant women with higher BMI (obese) before pregnancy. The control group (C) was 27 pregnant women with target BMI and physiological pregnancy. The BMI index: body weight [kg]/(height [m]² was assessed on the first obstetrical visit. The research material was the serum of pregnant women collected in the third trimester of pregnancy and umbilical cord blood collected immediately after delivery. Selected parameters of carbohydrate and lipid metabolism and adipokines were determined.

RESULTS

There were no statistically significant differences between the study group and the control group concerning the concentrations of insulin, glucose, VLDL, adiponectin, TNF-α, HOMA-IR, as well as LDH and cholesterol in maternal blood serum and umbilical cord blood serum. Total cholesterol and HDL in both maternal blood serum and umbilical cord blood were statistically significantly lower than those in the control group. The concentration of triglycerides (TG) and resistin in the blood serum of obese mothers were higher than those in the control group (p < 0.05). However, no statistically significant differences were found between the two groups regarding the concentrations of TG and resistin in the umbilical cord blood. The concentration of LDL cholesterol in the umbilical blood serum in the obese group was statistically significantly lower than that in the control group. The concentration of leptin in maternal blood serum and umbilical cord blood serum in the study group was statistically significantly higher than that in the control group.

CONCLUSIONS

Pregestational obesity does not substantially affect the basic parameters of carbohydrate metabolism in pregnant women, but it disturbs the lipid profile, which is manifested by a significant increase in triglycerides and a decrease in the level of HDL cholesterol in the serum. Preexisting obesity increases the concentration of leptin and resistin in the serum of pregnant women, which may be caused by the increased volume of adipose tissue. The concentrations of leptin and resistin in the blood of pregnant women correlate positively, and the concentrations of adiponectin and TNF-α negatively correlate with pre-pregnancy BMI values. There is a positive correlation between the concentration of leptin in the serum of umbilical cord blood and the birth weight of the newborn, which suggests that this parameter contributes to the pathomechanism of macrosomia.

The implications of the purinergic signaling throughout pregnancy

Purinergic signaling is a necessary mechanism to trigger or even amplify cell communication. Its ligands, notably adenosine triphosphate (ATP) and adenosine, modulate specific membrane-bound receptors in virtually all human cells. Regardless of the stage of the pregnancy, cellular communication between maternal, placental, and fetal cells is the paramount mechanism to sustain its optimal status. In this review, we describe the crucial role of purinergic signaling on the regulation of the maternal-fetal trophic exchanges, immune control, and endocrine exchanges throughout pregnancy. The nature of the modulation of both ATP and adenosine on the embryo-maternal interface, going through placental invasion until birth delivery depends on the general maternal-fetal health state and consequently on the selective activation of their specific receptors. In addition, an increasing number of studies have been demonstrating the pivotal role of ATP and adenosine in modulating deleterious effects of suboptimal conditions of pregnancy. Here, we discuss the role of purinergic signaling on the balance that coordinates the embryo-maternal exchanges and a promising therapeutic venue in the context of pregnancy disorders.

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.

Dietary Blueberry and Soluble Fiber Improve Serum Antioxidant and Adipokine Biomarkers and Lipid Peroxidation in Pregnant Women with Obesity and at Risk for Gestational Diabetes

Pregnancies affected by obesity are at high risk for developing metabolic complications with oxidative stress and adipocyte dysfunction contributing to the underlying pathologies. Few studies have examined the role of dietary interventions, especially those involving antioxidants including polyphenolic flavonoids found in fruits and vegetables on these pathologies in high-risk pregnant women. We conducted an 18 gestation-week randomized controlled trial to examine the effects of a dietary intervention comprising of whole blueberries and soluble fiber vs. control (standard prenatal care) on biomarkers of oxidative stress/antioxidant status and adipocyte and hormonal functions in pregnant women with obesity (n = 34). Serum samples were collected at baseline (<20 gestation weeks) and at the end of the study period (32-26 gestation weeks). Study findings showed maternal serum glutathione and antioxidant capacity to be significantly increased, and malondialdehyde to be decreased in the dietary intervention vs. control group (all p < 0.05). Among the adipokine biomarkers, serum plasminogen activator inhibitor-1 and visfatin, as biomarkers of adipocyte dysfunction and insulin resistance, were also decreased following dietary intervention (all p < 0.05). These findings support the need for supplementing maternal diets with berries and fiber to improve oxidative stress and risks of metabolic complications during pregnancy.

Interventional effect of dietary fiber on blood glucose and pregnancy outcomes in patients with gestational diabetes mellitus

To investigate the effect of dietary fiber on blood glucose and pregnancy outcomes in patients with gestational diabetes mellitus (GDM). One hundred and twelve patients with GDM in the second trimester of pregnancy were recruited from Women's Hospital, Zhejiang University School of Medicine. Patients were randomized into two groups with 56 in each group: the control group received basic nutrition support; while the dietary fiber group were given additional dietary fiber ( total dietary fiber per day) before meals in addition to basic nutrition support. Intervention for all cases lasted for 8 weeks. Fasting blood glucose and postprandial blood glucose (2 h BG) were measured every week, and oral glucose tolerance test (OGTT) was performed at 42 d postpartum to evaluate the glycemic outcomes. Perinatal outcomes were recorded. The dietary fiber intervention markedly improved 2 h BG in patients with GDM and significantly elevated the glucose compliance rate from the 3rd to 8th week compared to the control group ( <0.05 or <0.01). OGTT 2 h glucose and the incidence of impaired glucose tolerance in the dietary fiber group were significantly lower than those in the control group, while the glucose compliance rate was significantly higher than that in the control group (all <0.01). Moreover, the rates of adverse perinatal outcomes, such as premature rupture of membranes and neonatal hyperbilirubinemia were declined in the dietary fiber group (<0.05 or <0.01). Dietary fiber intervention can ameliorate hyperglycemia in GDM patients, improve perinatal outcomes and reduce the incidence of postpartum impaired glucose tolerance.

Resistin in pregnancy: Analysis of determinants in pairs of umbilical cord blood and maternal serum

Objective

Despite intensive research on the cytokine resistin only few studies investigated mother-newborn-pairs during healthy pregnancy and reported about interactions with clinical obstetric variables or other cytokines. Comparison of existing studies is difficult due to differences between assays, sample collection, gestational age, definition of healthy controls and patient characteristics. Furthermore, differences between rodent models and humans do not allow for a direct comparison.

Methods

In this cross-sectional, prospective study 109 healthy mother-newborn pairs were analyzed. Maternal venous blood samples were taken on admission to the labor ward; newborn venous blood samples were drawn from the placental part of the umbilical cord (UC), immediately after clamping. Resistin, leptin, adiponectin, TNF-α, IL-6 and brain derived neurotrophic factor (BDNF) serum concentrations were measured with commercially available immunoassays. Determinants of maternal and newborn resistin levels were analyzed using simple and multiple linear regression.

Results

UC resistin levels were higher than maternal concentrations (median 17.69 ng/mL, IQR 7.36 vs. median 8.04 ng/mL, IQR 4.30). Correlation between UC and maternal resistin levels was moderate (R = 0.503, p < 0.01). In multiple regression analysis levels of maternal resistin and newborn TNF-α remained significant determining factors for UC resistin levels. Gestational age and maternal BDNF-levels remained significant factors for maternal resistin levels.

Conclusion

In healthy, term newborns and their respective mothers a positive correlation between maternal and newborn levels and an association with gestational age around term can be found and point to a placental source of resistin. Further investigations are needed to clarify the possible contribution of transplacental transport of resistin into the fetal circulation. Except for gestational age most of the clinical obstetric variables tested do not seem to be determining factors for fetal or maternal resistin. Interactions of resistin with other cytokines like TNF-α and BDNF could be the missing link for the conflicting results in literature.

Maternal biomarker patterns for metabolism and inflammation in pregnancy are influenced by multiple micronutrient supplementation and associated with child biomarker patterns and nutritional status at 9-12 years of age

Maternal nutritional status influences fetal development and long-term risk for adult non-communicable diseases. However, the underlying mechanisms remain poorly understood. We examined whether biomarkers for metabolism and inflammation during pregnancy were associated with maternal health and with child biomarkers and health at 9-12 years of age in 44 maternal-child dyads from the Supplementation with Multiple Micronutrients Intervention Trial (SUMMIT, ISRCTN34151616) in Lombok, Indonesia. Archived blood for each dyad from maternal enrollment, later in pregnancy, postpartum, and from children at 9-12 years comprised 132 specimens. Multiplex microbead immunoassays were used to quantify vitamin D-binding protein (D), adiponectin (A), retinol-binding protein 4 (R), C-reactive protein (C), and leptin (L). Principal component analysis (PCA) revealed distinct variance patterns, i.e. principal components (PC), for baseline pregnancy, bp.pc1.D↓A↓R↓ and bp.pc2.C↓L↑; combined follow-up during pregnancy and postpartum, dp-pp.pc1.D↑↓A↑R↑↓L↓ and dp-pp.pc2.A↑C↑L↑; and children, ch.pc1.D↑R↑C↑ and ch.pc2.D↓A↑L↑. Maternal multiple micronutrient (MMN) supplementation led to an association of baseline maternal bp.pc2.C↓L↑ with decreased post-supplementation maternal dp-pp.pc2.A↑C↑L↑ (p = 0.022), which was in turn associated with both increased child ch.pc1.D↑R↑C↑ (p = 0.036) and decreased child BMI z-score (BMIZ) (p = 0.022). Further analyses revealed an association between maternal dp-pp.pc1.D↑↓A↑R↑↓L↓ and increased child BMIZ (p = 0.036). Child ch.pc1.D↑R↑C↑ was associated with decreased birth weight (p = 0.036) and increased child BMIZ (p = 0.002). Child ch.pc2.D↓A↑L↑ was associated with increased child BMIZ (p = 0.005), decreased maternal height (p = 0.030) and girls (p = 0.002). A pattern of elevated maternal adiponectin and leptin in pregnancy was associated with increased C-reactive protein, vitamin A, and D binding proteins pattern in children, suggesting biomarkers acting in concert may have qualitative as well as quantitative influence beyond single biomarker effects. Patterns in pregnancy proximal to birth were more associated with child status. In addition, child patterns were more associated with child status, particularly child BMI. MMN supplementation affects maternal biomarker patterns of metabolism and inflammation in pregnancy, and potentially in the child. However, child nutrition conditions after birth may have a greater impact on metabolism and inflammation.

Maternal circulating leptin profile during pregnancy and gestational diabetes mellitus

AIMS

To evaluate the difference in maternal circulating leptin profile between pregnant women with and without gestational diabetes mellitus (GDM).

METHODS

This is a nested case-control study embedded in the Born in Guangzhou Cohort Study in Guangzhou Women and Children's Medical Center, with 198 GDM cases and 192 controls included. Maternal plasma leptin profile was defined as leptin concentrations measured at early (baseline) and late pregnancy, as well as a ratio of concentration at late to that at early pregnancy (RL1L0). General linear regression was used to assess the associations between GDM and log-transformed leptin measurements.

RESULTS

Women with GDM had a higher baseline leptin concentration and lower RL1L0 compared to those without GDM. The log leptin concentration at baseline (β: 0.19, 95%CI: 0.04, 0.34) and the log RL1L0 (β: -0.22, 95%CI: -0.41, -0.03) were associated with GDM status. The RL1L0 decreased significantly along with the increase of 1-hour glucose and the difference between 1-hour and fasting glucose levels in both GDM and non-GDM women.

CONCLUSIONS

Women with GDM had a certain profile of circulating leptin, with higher baseline concentration but less increase during pregnancy, suggesting an impaired compensatory response to increasing insulin resistance along with the progress of pregnancy.

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.

Maternal serum level of resistin is associated with risk for gestational diabetes mellitus: A meta-analysis

BACKGROUND

Resistin is most likely involved in the pathogenesis of gestational diabetes mellitus (GDM), but the existing findings are inconsistent.

AIM

To review the literature investigating the associations of the risk of GDM with serum level of resistin.

METHODS

A systematic literature search was performed using MEDLINE, EMBASE, and Web of Science (all databases). This meta-analysis included eligible studies that: (1) investigated the relationship between the risk of GDM and serum resistin; (2) included GDM cases and controls without GDM; (3) diagnosed GDM according to the oral glucose-tolerance test; (4) were performed in humans; (5) were published as full text articles in English; and (6) provided data with median and quartile range, median and minimum and maximum values, or mean and standard deviation. The pooled standardized mean difference (SMD) and 95% confidence interval (CI) were calculated to estimate the association between the risk of GDM and serum resistin. To analyze the potential influences of need for insulin in GDM patients and gestational age at blood sampling, we performed a subgroup analysis. Meta-regression with restricted maximum likelihood estimation was performed to assess the potentially important covariate exerting substantial impact on between-study heterogeneity.

RESULTS

The meta-analysis for the association between serum resistin level and GDM risk included 18 studies (22 comparisons) with 1041 cases and 1292 controls. The total results showed that the risk of GDM was associated with higher serum resistin level (SMD = 0.250, 95%CI: 0.116, 0.384). The “after 28 wk” subgroup, “no need for insulin” subgroup, and “need for insulin” subgroup indicated that higher serum resistin level was related to GDM risk (“after 28 wk” subgroup: SMD = 0.394, 95%CI: 0.108, 0.680; “no need for insulin” subgroup: SMD = 0.177, 95%CI: 0.018, 0.336; “need for insulin” subgroup: SMD = 0.403, 95%CI: 0.119, 0.687). The “before 14 wk” subgroup, “14-28 wk” subgroup, and “no information of need for insulin” subgroup showed a nonsignificant association between serum resistin level and GDM risk (“before 14 wk” subgroup: SMD = 0.087, 95%CI: -0.055, 0.230; “14-28 wk” subgroup: SMD = 0.217, 95%CI: -0.003, 0.436; “no information of need for insulin” subgroup: SMD = 0.356, 95%CI: -0.143, 0.855). The postpartum subgroup included only one study and showed that higher serum resistin level was related to GDM risk (SMD = 0.571, 95%CI: 0.054, 1.087) The meta-regression revealed that no need for insulin in GDM patients, age distribution similar between cases and controls, and ELISA all had a significant impact on between-study heterogeneity.

CONCLUSION

This meta-analysis supports that the maternal serum resistin level is associated with GDM risk.

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.

Relationship between advanced glycation end products and gestational diabetes mellitus

Objective: To investigate the levels of and dynamic changes of advanced glycation end products (AGEs) in maternal plasma during pregnancy and explore the association between these levels and gestational diabetes mellitus (GDM). Methods: This study recruited 90 GDM women and 90 healthy pregnant controls. The women received prenatal care and were hospitalized for delivery in Peking University First Hospital in China between October 2015 and April 2016. The patients were recruited and provided blood samples during gestational weeks 24-29. The levels of AGEs, TNF-α, hs-CRP, plasma glucose, and FINS and lipid profiles were measured, and HOMA-IR was calculated. New blood samples were collected and AGE was measured again in the two groups at 33-41 weeks of gestation to identify its dynamic changes. Results: The levels of AGEs were significantly higher in the GDM group than in the NGT group at both 24-29 weeks (473.65 ± 105.32 versus 324.36 ± 57.86 ng/L; p < .001) and 33-41 weeks (533.47 ± 146.95 versus 315.50 ± 77.79 ng/L; p < .001), and plasma levels of TNF-α and hs-CRP were significantly higher in the GDM group than in the NGT group (282.58 ± 45.85 versus 177.54 ± 35.14 pg/mL; 1.11 ± 0.25 versus 0.6 ± 0.19 µg/mL; p < .001), even after adjusting for other confounding factors, AGE levels were positively correlated with the levels of 2hPG (p = .003), TNF-α (p = .005), and hs-CRP (p < .001). A logistic regression analysis showed that AGE (OR = 1.037, 95%CI: 1.017 ∼ 1.058) and TNF-α (OR = 1.115, 95%CI: 1.048 ∼ 1.186) levels were independent risk factors for GDM. In the GDM group, the concentration of AGEs was significantly higher at 33-41 weeks than at 24-29 weeks (p = .001). In the NGT group, there was no significant change in the concentration of AGEs between the two gestational periods (p = .388). Conclusions: Plasma levels of AGEs are associated with GDM. During pregnancy, the changes observed in the levels of AGEs were different between GDM and normal pregnancies.

Dietary patterns and their association with adiponectin and leptin concentrations throughout pregnancy: a prospective cohort

The aim of this study was to evaluate the association of dietary patterns (DP) with maternal adiposity indicators, leptin, adiponectin and insulin concentrations during pregnancy. A prospective cohort of pregnant women followed up at the 5th-13th, 20th -26th and 30th-36th gestational weeks and 30-40 d postpartum was conducted in Rio de Janeiro. A FFQ was administered in the third trimester (30th-36th gestational weeks). The reduced rank regression procedure was used to identify DP that explain response variables (dietary fibre and total fat) related to indicators of maternal adiposity (postpartum weight retention and gestational weight gain (GWG) adequacy), and plasma leptin, adiponectin and insulin concentrations. The associations between tertiles of DP and the outcomes were determined using logistic regression or longitudinal linear mixed-effect regression models. The mean daily energy intake during pregnancy was 10 104 (sd 3234) kJ (2415 (sd 773) kcal), and GWG was 11·9 (sd 4·2) kg. In all, 40 % of women presented pre-gestational overweight/obesity. Excessive GWG occurred in 34·7 % of pregnant women and 56·6 % were overweight/obese at postpartum. The 'common-Brazilian' DP (characterised by higher intake of beans, rice and lower intake of fast food/snacks, candies/table sugar and processed meats/bacon) was positively associated with adiponectin (β=1·07; 95 % CI 0·17, 1·98). The 'Western' DP (characterised by higher intake of fast food/snacks and processed meat/bacon and lower intake of noodles/pasta/roots/tubers and sodas) was negatively associated with adiponectin (β=-1·11; 95 % CI -2·00, -0·22) and positively associated with leptin concentrations (β=64·9; 95 % CI 22·8, 107·0) throughout pregnancy. It may be suggested that the 'common-Brazilian' is a healthy DP and beneficial for serum concentrations of adiponectin and leptin.

Leptin and soluble leptin receptor in association with gestational diabetes: a prospective case-control study

PURPOSE

To assess the association of serum leptin and its receptor (SLeptinR) with the risk of gestational diabetes mellitus (GDM) and to evaluate the longitudinal circulation of these peptides in pregnancy.

METHODS

This study consisted of 53 subjects diagnosed with GDM and 43 normal glucose tolerance (NGT) pregnant women. Serum leptin and SLeptinR were measured at 24-28 weeks, prior and after delivery, and post-puerperium.

RESULTS

Lower levels of leptin and SLeptinR were observed in GDM compared to NGT. Leptin [OR 0.97 (95% CI 0.94-1.0)] and SLeptinR [OR 0.86 (95% CI 0.79-0.93]) were inversely associated with GDM. Participants in the lowest tertile for leptin and SLeptinR had a 2.8-fold (95% CI 1.0-7.6) and a 5.7-fold (95% CI 1.9-17.3) higher risk of developing GDM compared with the highest tertile, respectively. These relationships were attenuated after adjustment for covariates. In both the groups, peak leptin was observed at 24-28 weeks, decreasing continuously during pregnancy (p > 0.05) and after delivery (p < 0.017). SLeptinR level increased (p < 0.001) during pregnancy and decreased (p < 0.005) after delivery in GDM, however, levels remained the same in NGT. In GDM, leptin and SLeptinR was positively and inversely correlated with BMI and HOMA-IR at 24-28 weeks and post-puerperium, respectively. The cord levels of both leptin and SLeptinR were lower than maternal levels. There were no significant differences in serum cord leptin and SLeptinR levels between the groups.

CONCLUSION

Leptin and SLeptinR are independently and inversely associated with GDM. Lower levels of these peptides may play an important role in the pathophysiology of GDM and pre-diabetic state in post-puerperium.

Association of genetic variants in RETN, NAMPT and ADIPOQ gene with glycemic, metabolic traits and diabetes risk in a Chinese population

Abnormal serum levels of adipokine have been established to be a strong predictor of developing several human diseases including type 2 diabetes mellitus (T2DM). Association studies have reported several genetic variants in genes coding adipokines with contributions to T2DM susceptibility as well as some glycemic and metabolic traits, of which the single nucleotide polymorphisms (SNPs) of RETN, NAMPT, and ADIPOQ gene were well documented. However, little is known about contributions of these SNPs to above phenotypes in Chinese. In the current study, with availably quantitative glycemic and metabolic data from a total of 185 T2DM patients and 191 healthy controls, we tested associations between four SNPs of RETN, NAMPT, ADIPOQ gene and 13 glycemic and metabolic traits. The results showed that the rs1862513 and rs34861192 of RETN gene were functional and negatively correlated with the levels of serum creatinine and cholesterol, respectively. The rs16861194 of ADIPOQ gene was positively correlated with the aspartate aminotransferase (AST) and AST/alanine aminotransferase level. Moreover, the rs34861192 and rs13237989 of NAMPT gene synergistically affected the levels of insulin and glycemic index. However, due to the limited sample size, only the rs16861194 exerted a significant increased risk on T2DM. These results underscore the contributions of SNPs in RETN, NAMPT, ADIPOQ gene to glycemic and metabolic traits as well as T2DM susceptibility in Chinese.

Specific Metabolic Characteristics of Women With Former Gestational Diabetes: the Importance of Adipose Tissue

Women with a positive history of gestational diabetes mellitus (GDM) face a higher risk of developing type 2 diabetes mellitus (T2DM) and metabolic syndrome later in life. The higher risk of these metabolic complications is closely associated with adipose tissue. In this review, the importance of adipose tissue is discussed in relation to GDM, focusing on both the quantity of fat deposits and the metabolic activity of adipose tissue in particular periods of life: neonatal age, childhood, adolescence, and pregnancy followed by nursing. Preventive measures based on body composition and lifestyle habits with special attention to the beneficial effects of breastfeeding are also discussed.

Resistin role in development of gestational diabetes mellitus

Diabetes is estimated to be one of the major causes of deaths in most countries due to its high prevalence rate, which was 8.8% in 2015. Hyperglycemia detected during pregnancy is known as gestational diabetes mellitus and it increases the potential risk of development of Type 2 diabetes in mothers with its varying prevalence rate of 1-14% in different populations. It also leads to the higher risk of developing abnormal glucose tolerance and obesity in their child at an early age. Recent studies show that potential mediators of insulin resistance such as adipokines - adiponectin, leptin and resistin are important for glucose and lipid metabolism. Adipokines are directly involved in the regulation of insulin secretion and insulin sensitivity in the liver, muscle and adipose tissue. It is also involved in inflammation, adipose tissue accumulation, adverse fat distribution and subsequently affects glucose metabolism. This review highlights the role of resistin (an adipokine) in the development of gestational diabetes mellitus.

First-trimester multimarker prediction of gestational diabetes mellitus using targeted mass spectrometry

AIMS/HYPOTHESIS

Gestational diabetes mellitus (GDM) is associated with an increased risk of pre-eclampsia, macrosomia and the future development of type 2 diabetes mellitus in both mother and child. Although an early and accurate prediction of GDM is needed to allow intervention and improve perinatal outcome, no single protein biomarker has yet proven useful for this purpose. In the present study, we hypothesised that multimarker panels of serum proteins can improve first-trimester prediction of GDM among obese and non-obese women compared with single markers.

METHODS

A nested case-control study was performed on first-trimester serum samples from 199 GDM cases and 208 controls, each divided into an obese group (BMI ≥27 kg/m(2)) and a non-obese group (BMI <27 kg/m(2)). Based on their biological relevance to GDM or type 2 diabetes mellitus or on their previously reported potential as biomarkers for these diseases, a number of proteins were selected for targeted nano-flow liquid chromatography (LC) MS analysis. This resulted in the development and validation of a 25-plex multiple reaction monitoring (MRM) MS assay.

RESULTS

After false discovery rate correction, six proteins remained significantly different (p<0.05) between obese GDM patients (n=135) and BMI-matched controls (n=139). These included adiponectin, apolipoprotein M and apolipoprotein D. Multimarker models combining protein levels and clinical data were then constructed and evaluated by receiver operating characteristic (ROC) analysis. For the obese, non-obese and all GDM groups, these models achieved marginally higher AUCs compared with adiponectin alone.

CONCLUSIONS/INTERPRETATION

Multimarker models combining protein markers and clinical data have the potential to predict women at a high risk of developing GDM.

Relationships between plasma leptin levels, leptin G2548A, leptin receptor Gln223Arg polymorphisms and gestational diabetes mellitus in Chinese population

The purposes of this study were to examine concentrations of leptin and biochemical parameters in gestational diabetes mellitus (GDM) patients and normal glucose tolerance (NGT) individuals, and also to explore the links of leptin (LEP) G2548A and leptin receptor (LEPR) Gln223Arg polymorphisms with leptin levels and GDM risk among Chinese. Our study included 357 GDM and 355 NGT individuals who were at 24~30 gestational weeks. Plasma leptin and insulin levels were analyzed by ELISA. Gene polymorphisms were genotyped using TaqMan real-time polymerase chain reaction assay. The results showed that plasma leptin levels were significantly higher in the impaired fasting glucose (IFG) group than NGT group (34.35 (26.54, 56.48) ng/mL vs 26.31 (17.99, 37.87) ng/mL, P < 0.05). Plasma leptin levels correlated with plasma fasting insulin levels, pre-pregnant body mass index, homeostasis model assessment-insulin resistance and quantitative insulin sensitivity check index both in GDM and NGT group (P < 0.05). However, neither LEP G2548A nor LEPR Gln223Arg polymorphisms were significantly associated with GDM risk and plasma leptin levels (P > 0.05). Our findings showed that high leptin level was associated with GDM. And larger and more rigorous researches were needed to further explore the association of LEP and LEPR gene polymorphisms and GDM among Chinese population.

Impact of Systemic Inflammation on the Progression of Gestational Diabetes Mellitus

With increasing rates of obesity and new diagnostic criteria for gestational diabetes mellitus (GDM), the overall prevalence of GDM is increasing worldwide. Women with GDM have an increased risk of maternal and fetal complications during pregnancy as well as long-term risks including higher prevalence of type 2 diabetes mellitus and cardiovascular disease. In recent years, the role of immune activation and inflammation in the pathogenesis of GDM has gained increasing attention. This monograph explores the current state of the literature as regards the expression of markers of inflammation in the maternal circulation, placenta, and adipose tissue of women with GDM.

First trimester screening for gestational diabetes mellitus by maternal factors and markers of inflammation

OBJECTIVE

To examine the potential role of maternal serum levels of tumor necrosis factor-α (TNF-α) and high sensitivity C-reactive protein (Hs-CRP) in the first trimester of pregnancy in the prediction of gestational diabetes mellitus (GDM).

METHODS

Maternal serum TNF-α and Hs-CRP concentrations were measured in a case-control study of singleton pregnancies at 11-13 weeks' gestation, which included 200 cases that subsequently developed GDM and 800 unaffected controls. Measured levels of TNF-α and Hs-CRP were expressed as multiples of the median (MoM) after adjustment for maternal characteristics and history. The performance of screening for GDM by maternal factors and MoM values of TNF-α and Hs-CRP was evaluated by the area under the receiver operating characteristic curves (AUROC).

RESULTS

In the GDM group, compared to the normal group, the median TNF-α was significantly increased (1.303 MoM, interquartile range [IQR] 1.151-1.475 vs. 1.0 MoM, IQR 0.940-1.064; p=0.031) and the median Hs-CRP was not significantly different (1.113 MoM, IQR 0.990-1.250 vs. 1.0 MoM, IQR 0.943-1.060; p=0.084). In the prediction of GDM, the AUROC for maternal characteristics with TNF-α or Hs-CRP was not significantly different than the AUROC for maternal characteristics alone (p=0.5055 and p=0.2197, respectively).

CONCLUSIONS

In pregnancies that develop GDM there is no evidence of an inflammatory response at 11-13 weeks' gestation and the levels of serum TNF-α and Hs-CRP are not useful in first-trimester screening for GDM.

Serum saturated fatty acid decreases plasma adiponectin and increases leptin throughout pregnancy independently of BMI

OBJECTIVE

The aim of this study was to investigate whether serum concentrations of total saturated fatty acids (SFAs), polyunsaturated fatty acids (PUFAs), and their fractions are associated with plasma adiponectin and leptin concentrations throughout pregnancy.

METHODS

A prospective cohort of 201 pregnant women was followed from gestational weeks 5 to 13, 20 to 26, and 30 to 36. Blood samples were collected at the three visits after 12 h of fasting. Fatty acid concentrations were determined using fast gas-liquid chromatography. Plasma adiponectin (μg/mL) and leptin (ng/dL) concentrations were evaluated using enzyme-linked immunosorbent assay kits. Statistical analyses included median adipokine concentrations according to the tertiles of fatty acid distribution and multiple linear mixed-effect models adjusted for body mass index, gestational age, total energy intake, alcohol consumption, and smoking.

RESULTS

Women classified in the third SFA concentration tertile had lower median values of adiponectin compared with those in the first tertile ([first trimester: first tertile = 5.36; third tertile = 5.00]; [second trimester: first tertile = 6.39; third tertile = 4.47]; [third trimester: first tertile = 6.46; third tertile = 4.60]). Similar trends were observed for the 14:0, 16:0 and 18:0 fractions. In the multiple longitudinal models, total SFA (β = -41.039; P = 0.008) and 16:0 were negatively associated with plasma adiponectin (16:0, β = -0.511; P = 0.001). Total PUFA ω-6 (β = 28.961; P = 0.002) and 18:2 ω-6 (β = 0.259, P = 0.006) were positively associated with the adiponectin. Total SFA (β = 0.110, P = 0.007), 14:0 (β = 0.072, P = 0.011), and 20:3 ω-6 (β = 0.039; P = 0.035) were positively associated with plasma leptin.

CONCLUSIONS

Total serum SFA and the 16:0 fraction were negatively associated with plasma adiponectin and positively associated with leptin concentrations. Total ω-6 PUFA was positively associated only with plasma adiponectin concentrations throughout pregnancy.

Screening of subclinical hypothyroidism during gestational diabetes in Pakistani population

OBJECTIVE

The increased prevalence of adverse effects of altered thyroid functions in pregnancy inspired us to study the frequency of subclinical hypothyroidism (SCH) and the relationship with glycaemic control and foetal weight in pregnant females with and without gestational diabetes mellitus (GDM) in Pakistani population.

PATIENTS AND METHODS

Five hundred and eight pregnant females were enrolled and grouped as per the International Diabetes Association criteria into GDM (n = 208) and healthy control (n = 300). Random blood glucose (RBG), thyroid function tests, anthropometric analysis and foetal ultra sound scans were performed on all study subjects. Data were analysed using Mann-Whitney U test and Chi-square test wherever applicable. Spearman correlation and multiple regression analysis were performed. p values of <0.05 was considered significant.

RESULTS

A total of 61.5% GDM subjects depicted SCH with normal circulating T4 and T3 versus 6.0% healthy controls (p-value < 0.001). Moreover, TSH remained independently associated with RBG (r = 0.109; p < 0.05), poor glycaemic control (r = 0.227; p < 0.001) and negatively associated with foetal growth (r = -0.206; p < 0.001).

CONCLUSION

The detection of high TSH with normal T3 and T4 in females with GDM strongly emphasises the need of thyroid screening as a routine in all antenatal clinics.

Inflammation in maternal obesity and gestational diabetes mellitus

BACKGROUND

The prevalence of maternal obesity is rising rapidly worldwide and constitutes a major obstetric problem, increasing mortality and morbidity in both mother and offspring. Obese women are predisposed to pregnancy complications such as gestational diabetes mellitus (GDM), and children of obese mothers are more likely to develop cardiovascular and metabolic disease in later life. Maternal obesity and GDM may be associated with a state of chronic, low-grade inflammation termed "metainflammation", as opposed to an acute inflammatory response. This inflammatory environment may be one mechanism by which offspring of obese women are programmed to develop adult disorders.

METHODS

Herein we review the evidence that maternal obesity and GDM are associated with changes in the maternal, fetal and placental inflammatory profile.

RESULTS

Maternal inflammation in obesity and GDM may not always be associated with fetal inflammation.

CONCLUSION

We propose that the placenta 'senses' and adapts to the maternal inflammatory environment, and plays a central role as both a target and producer of inflammatory mediators. In this manner, maternal obesity and GDM may indirectly program the fetus for later disease by influencing placental function.

Adipokines in human reproduction

Adipose tissue communicates with other central and peripheral organs by the synthesis and release of substances called adipokines. The most studied adipokine is leptin but others have been recently identified including resistin, adiponectin, chemerin, omentin and visfatin. These adipokines have a critical role in the development of obesity-related complications and inflammatory conditions. However, they are also involved in other functions in the organism including reproductive functions. Indeed, many groups have demonstrated that adipokine receptors, such as adiponectin and chemerin, but also adipokines themselves (adiponectin, chemerin, resistin, visfatin and omentin) are expressed in human peripheral reproductive tissues and that these adipokines are likely to exert direct effects on these tissues. After a brief description of these new adipokines, an overview of their actions in different human reproductive organs (hypothalamus, pituitary, ovary, testis, uterus and placenta) will be presented. Finally, comments will be made on the eventual alterations of these adipokines in reproductive disorders, with special attention to polycystic ovary syndrome, a disease characterized by dysfunction of gonadal axis and systemic nerve endocrine metabolic network with a prevalence of up to 10% in women of reproductive age.