C-reactive protein and tumor necrosis factor-alpha in gestational hyperglycemia

Beta-cell compensation and gestational diabetes

Gestational diabetes mellitus (GDM) is characterized by glucose intolerance in pregnant women without a previous diagnosis of diabetes. While the etiology of GDM remains elusive, the close association of GDM with increased maternal adiposity and advanced gestational age implicates insulin resistance as a culpable factor for the pathogenesis of GDM. Pregnancy is accompanied by the physiological induction of insulin resistance in the mother secondary to maternal weight gain. This effect serves to spare blood glucose for the fetus. To overcome insulin resistance, maternal β-cells are conditioned to release more insulin into the blood. Such an adaptive response, termed β-cell compensation, is essential for maintaining normal maternal metabolism. β-cell compensation culminates in the expansion of β-cell mass and augmentation of β-cell function, accounting for increased insulin synthesis and secretion. As a result, a vast majority of mothers are protected from developing GDM during pregnancy. In at-risk pregnant women, β-cells fail to compensate for maternal insulin resistance, contributing to insulin insufficiency and GDM. However, gestational β-cell compensation ensues in early pregnancy, prior to the establishment of insulin resistance in late pregnancy. How β-cells compensate for pregnancy and what causes β-cell failure in GDM are subjects of investigation. In this mini-review, we will provide clinical and preclinical evidence that β-cell compensation is pivotal for overriding maternal insulin resistance to protect against GDM. We will highlight key molecules whose functions are critical for integrating gestational hormones to β-cell compensation for pregnancy. We will provide mechanistic insights into β-cell decompensation in the etiology of GDM.

Role of Oxidative Stress and Inflammation in Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is one of the most common pregnancy complications. It is related to several gestational and fetal adverse outcomes. Moreover, women with GDM and their infants have a high risk of developing type 2 diabetes in the future. The pathogenesis of GDM is not completely understood; nevertheless, two factors that contribute to its development are oxidative stress and inflammation. Oxidative stress and inflammation are related; reactive oxygen species (ROS) production can activate inflammatory cells and enhance the production of inflammatory mediators. Inflammation, in turn, leads to an increased ROS release, causing a vicious circle to ensue. Inflammatory responses can be achieved via the activation of the NF-κB signaling pathway. Herein, we review the English literature regarding oxidative stress and inflammation evaluated simultaneously in the same population, attempting to identify mechanisms through which these factors contribute to the development of GDM. Furthermore, the modulation of oxidative stress and inflammation by different therapies used in women with GDM and in cell models of GDM is included in the review. Probiotics and nutrient supplementations have been shown to reduce biomarkers of inflammation and oxidative stress in vitro and in women with GDM.

Longitudinal assessment of inflammatory markers in the peripartum period by depressive symptom trajectory groups

Objective

Mechanisms driving temporal fluctuations of inflammatory markers during pregnancy, and how these might differ between distinct perinatal depressive trajectories, are not well understood. The aim of this study was to investigate cytokines levels over the course of pregnancy in women with different trajectories of depressive symptoms peripartum, and relate the levels to levels of non-pregnant controls.

Methods

Based on the Edinburgh Postnatal Depression Scale and/or selective serotonin reuptake inhibitors use, 131 women were categorized into: no (n = 65); antepartum (APD, n = 19), postpartum (PPD, n = 17) and persistent (n = 30) depressive symptoms. Plasma samples (n = 386) were analyzed for levels of interleukin (IL)-8, IL-18, Tumor necrosis factor-α, macrophage colony-stimulating factor (M-CSF), vascular endothelial growth factor A (VEGF-A) and fractalkine, at four different time-points (twice during pregnancy, during childbirth, and postpartum) using Bio-Plex Pro Human Cytokine Assays. Generalized linear mixed models were applied to analyze the associations between cytokine levels, time-point, perinatal depressive symptom trajectory group and their interaction.

Results

For all markers but VEGF-A, pregnancy was associated with higher cytokine levels compared to the non-pregnant controls, with delivery being the most prominent time-point. For M-CSF, IL-18 and VEGF-A, levels were back to the non-pregnant status at postpartum week 8. An effect of perinatal depressive symptom trajectory groups on cytokine levels was found for VEGF-A. Women with PPD and women with APD had lower levels of VEGF-A throughout the study period compared to women with persistent depression, and women with PPD had lower levels compared to non-depressed women.

Conclusions

Lower levels of VEGF-A were noted among women in some trajectories of depressive symptoms peripartum. The peripartum period is a time of tremendous immune system adaptations. Standardization of time-points for cytokine measurements in studies of perinatal depression are important in order to draw valid conclusions on the role of the immune system in perinatal depression.

Exploring the Regulation of Jiangtang Tiaozhi Formula on the Biological Network of Obese T2DM Complicated With Dyslipidemia Based on Clinical Transcriptomics

OBJECTIVE

To use systems biology to explore the biomolecular network mechanism of the Jiangtang Tiaozhi Recipe (JTTZR) in the intervention of obese Type 2 diabetes (T2DM) patients with dyslipidemia.

METHODS

Twelve patients with obese type 2 diabetes mellitus and dyslipidemia (traditional Chinese medicine syndrome differentiation was excess heat syndrome of the stomach and intestines) were treated with JTTZR for 24 weeks, and 12 patients were included in the healthy control group. First, blood samples from 6 patients in each group (disease group before treatment, disease group after treatment, and healthy control group) were collected for RNA microarray analysis. Quantitative polymerase chain reaction (qPCR) was used to validate these target lncRNAs and mRNAs. Finally, a detailed analysis of the differences in the disease group before treatment vs. the healthy control group and the disease group after treatment vs. the disease group before treatment was undertaken. In addition, we focused on disease-related pathways and analyzed the correlation between the differential expression of target lncRNAs and clinical indicators.

RESULTS

(1) Disease group before treatment vs. healthy control group: There were 557 up-regulated lncRNAs, 273 down-regulated lncRNAs, 491 up-regulated mRNAs, and 1639 down-regulated mRNAs. GO analysis and pathway analysis showed that T2DM may be related to cell proliferation in the forebrain, post-embryonic organ development, calcium signaling pathway. qPCR validation showed that the expression of XLOC-005590 and HNF1A-AS1 as target lncRNAs increased, and this was verified by gene chip analysis. (2) Disease group after treatment vs. disease group before treatment: 128 lncRNAs were upregulated, 32 lncRNAs were downregulated, 45 mRNAs were upregulated, and 140 mRNAs were downregulated. GO analysis and pathway analysis showed that JTTZR may treat T2DM through endosome transport, the insulin signaling pathway, and glycine, serine, and threonine metabolism. qPCR validation showed that in the healthy control group, XLOC_005590 was upregulated, whereas the downstream gene (ECI2) was downregulated in the disease group before treatment. However, after 24 weeks of intervention with JTTZR, XLOC_005590 was downregulated and ECI2 was upregulated compared with the disease group before treatment (0 weeks) (P <0.05).

CONCLUSION

JTTZR may interfere in patients with obese T2DM with dyslipidemia by regulating pathways such as fatty acid degradation, glycolysis/gluconeogenesis, and pyruvate metabolism.

Myrtenol alleviates oxidative stress and inflammation in diabetic pregnant rats via TLR4/MyD88/NF-κB signaling pathway

Gestational diabetes mellitus (GDM) is a special kind of diabetes that arises only during pregnancy. A woman with GDM has a higher risk of developing type-2 diabetes and other metabolic diseases. In this exploration, we intended to scrutinize the therapeutic actions of Myrtenol against the streptozotocin (STZ)-provoked GDM in rats. GDM was provoked in the pregnant rats via injecting the 1% of STZ (25 mg/kg) and then treated with the 50 mg/kg of myrtenol. The glucose level and bodyweight of animals were noted. The lipid profile, that is, total cholesterol, triglycerides, low-density lipoprotein, and high-density lipoprotein (HDL) was determined by respective kits. The lipid peroxidation and antioxidants status were examined using assay kits. The status of proinflammatory markers was investigated by assay kits. The messenger RNA (mRNA) expressions of TLR4/MyD88/NF-κB signaling proteins were studied by reverse transcription polymerase chain reaction analysis. The hepatic and pancreatic tissues were examined microscopically. Myrtenol treatment notably decreased the status of blood glucose and lipid profile and improved the HDL in the GDM rats. The status of lipid peroxidation and inflammatory markers were substantially reduced by the myrtenol and it enhanced the antioxidants status of GDM animals. Myrtenol treatment remarkably downregulated the mRNA expressions of TLR4/MyD88/NF-κB signaling proteins. The histological findings also proved the therapeutic actions of myrtenol. Altogether, the findings of this investigation unveiled the therapeutic actions of the myrtenol against the STZ-provoked GDM in rats. Myrtenol could be a promising therapeutic agent to treat GDM in the future.

Vitamin A and Its Multi-Effects on Pancreas: Recent Advances and Prospects

Vitamin A (VA), which is stored in several forms in most tissues, is required to maintain metabolite homeostasis and other processes, including the visual cycle, energy balance, epithelial cell integrity, and infection resistance. In recent years, VA molecules, also known as retinoids, have been extensively explored and used in the treatment of skin disorders and immune-related tumors. To date, several observational and interventional studies have explored the relationship between VA status and the pathogenesis of diabetes. In particular, VA micronutrients have been shown to regulate pancreatic development, β-cell function, pancreatic innate immune responses, and pancreatic stellate cells phenotypes through multiple mechanisms. However, there are still many problems to be proven or resolved. In this review, we summarize and discuss recent and available evidence on VA biological metabolism in the pancreas. Analysis of the effects of VA on metabolism in the pancreas will contribute to our understanding of the supportive physiological roles of VA in pancreas protection.

Hypovitaminosis D Is Associated with Some Metabolic Indices in Gestational Diabetes Mellitus

Background

Gestational diabetes mellitus (GDM), a pregnancy complication, is defined as any degree of glucose intolerance with onset or first recognition during pregnancy. Vitamin D deficiency and insufficiency has recently been recognized as a contributing factor to the pathogenesis of GDM, and this link might be associated with hyperglycemia, insulin resistance, and inflammation, which are implicated in GDM.

Objectives

This study aims at investigating the relationship between vitamin D, fasting plasma glucose (FPG), insulin, zinc, ferritin, and high-sensitivity C-reactive protein (CRP) in GDM.

Method

A case-control study in which 80 women attending the antenatal clinic of University College Hospital (UCH), Ibadan, Nigeria, were recruited; the women were grouped into controls (40 nondiabetic pregnant women) and cases (40 pregnant women with GDM). Blood samples were taken at the second trimester, and metabolites were quantified by standard laboratory methods. Student's t test and Pearson correlation were used to compare variables and determine the relationship between variables, respectively.

Results

Results showed significant (p < 0.05) low levels of serum vitamin D and zinc, and significant (p < 0.05) higher levels of FPG and serum insulin, ferritin, and CRP in the GDM group compared to the control group. In the GDM group, a positive weak relationship was observed between vitamin D and zinc (r = 0.18, p < 0.05), while vitamin D was inversely correlated with FPG, serum insulin, ferritin, and CRP (r = -0.23, -0.21, -0.20, -0.46, respectively, p < 0.05).

Conclusion

This study suggests that hypovitaminosis D might be associated with glucose intolerance, insulin insensitivity, and inflammation, which are factors implicated in the development and progression of GDM.

DNA methylation patterns in T lymphocytes are generally stable in human pregnancies but CD3 methylation is associated with perinatal psychiatric symptoms

Objectives

To determine whether DNA methylation patterns in genes coding for selected T-lymphocyte proteins are associated with perinatal psychiatric distress or with complications of pregnancy.

Methods

T lymphocyte DNA was obtained from pregnant women across three time points in pregnancy and the postpartum period and epigenetic patterns were assessed using Illumina 450 ​K Methylation Beadchips. Seven selected genes critical for T cell function were analyzed for methylation changes during pregnancy and for associations of methylation patterns with psychiatric distress or with pregnancy complications, with particular attention paid to spatial aggregations of methyl groups, termed ‘hotspots,’ within the selected genes.

Results

In the candidate gene approach, DNA methylation density within a single cluster of 9 contiguous CpG loci within the CD3 gene was found to be strongly associated with anxiety and depression in mid- and late pregnancy, and weakly associated with the presence of complications of pregnancy. Average DNA methylation density across each of the seven genes examined, and assay-wide, was found to be relatively stable across pregnancy and postpartum, but methylation within the CD3 hotspot was more malleable and changes over time were coordinated across the nine cytosines in the hotspot. CD3 CpGs did not pass array-wide tests for significance, but CpG clusters in two other genes, DTNBP1 and OXSR1, showed array-wide significant associations with anxiety.

Conclusions

Despite the need for tolerating the fetal hemi-allograft, overall DNA methylation patterns in T lymphocytes are generally stable over the mid to late course of human pregnancies and postpartum. However, site-specific changes in DNA methylation density in CD3 appear linked to both symptoms of depression and anxiety in pregnancy and, less strongly, to adverse pregnancy outcomes.

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Associations exist between DNA methylation density in T cells and measures of stress and mental health in pregnant women.

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Global DNA methylation density is generally stable over the course of pregnancy.

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A subregion within the CD3 gene has unusually variable DNA methylation density and is associated with anxiety and depression.

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Spatial and gene specificity may be important elements of epigenetic regulation of immune function in pregnancy.

The Association of Maternal Protein Intake during Pregnancy in Humans with Maternal and Offspring Insulin Sensitivity Measures

The purpose of this review is to critically evaluate the studies assessing the relations between protein intake during human pregnancy and insulin sensitivity measures in the mother and offspring, and to get a better understanding of the knowledge gaps that still exist. Overall, there is insufficient evidence to conclude about implications of higher amounts of protein intake during pregnancy on maternal or offspring insulin sensitivity. However, studies show a relation between protein quality and insulin sensitivity, such that animal protein may be associated with negative outcomes and plant protein may be associated with positive insulin sensitivity outcomes. There is an urgent need for standardized studies using comparable terminology to evaluate any potential relations between insulin sensitivity in mothers and offspring and truly low and high maternal protein intake while maintaining eucaloric balance to better inform about optimal protein dosage and quality during this period.

Functional Defects of Regulatory T Cell Through Interleukin 10 Mediated Mechanism in the Induction of Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is a metabolic and low-grade inflammatory disease most commonly found in pregnant women with high body mass index and non-Caucasian ethnicities; however, not all women of high-risk groups develop GDM. We hypothesized that regulatory T cells (Tregs) might present a role in suppressing GDM development. To this end, 55 high-risk women at early pregnancy (first trimester) were recruited, and 21 of them developed GDM while the other 34 did not. Compared to those subjects who did not develop GDM (non-GDM), the patients who developed GDM presented reduced levels of Tregs and elevated levels of serum interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha). The Tregs in the GDM group also presented reduced levels of transforming growth factor beta and IL-10, compared with the non-GDM group. The frequency of circulating Tregs and serum TNF-alpha level were inversely correlated. In addition, addition of Tregs from non-GDM patients, but not those from GDM patients, significantly suppressed the interferon gamma and TNF-alpha production by effector T cells through IL-10-mediated mechanisms, suggesting a functional defect in Tregs from GDM subjects. Together, these data indicated that the presence of functional Tregs could protect the pregnant women from GDM development by suppressing pro-inflammatory responses and that the dysregulation of Tregs early in pregnancy elevated the risk of GDM.

The prevalence of elevated high-sensitivity C-reactive protein in normal pregnancy and gestational diabetes mellitus

Objective:

The objective of this study is to determine the prevalence of elevated high-sensitivity C-reactive protein (hs-CRP) in normal pregnancy and gestational diabetes mellitus (GDM) and to compare the prevalence in both groups.

Materials and Methods:

We conducted a case–control study between April 2015 and April 2016. Statistical analysis was performed by the SPSS program version 17. Categorical variables were analyzed using either the Chi-square test or Fisher's exact test. Pregnant women who underwent oral glucose tolerance test at 24–28 weeks of gestation were enrolled. We took 25 women with GDM as cases and 25 normal pregnant as control. These patients were analyzed for the level of hs-CRP.

Results:

The prevalence of elevated hs-CRP in controls was 28% whereas in cases was 76%, with a P = 0.002 which is significant in this study. When compared to elevated hs-CRP in GDM with body mass index and gravid state a P = 0.430, 0.378 was obtained respectively which was not significant whereas age had a P = 0.049 which was significantly associated with elevated hs-CRP (≥3 mg/L).

Conclusion:

Our result shows an increased level of hs-CRP in GDM as compared to normal pregnant subjects. In this study, we also observed an association of increasing age with elevated level of hs-CRP in GDM. Therefore, hs-CRP can be used as a screening tool for early detection and risk assessment of GDM.

Positive Correlation between Enhanced Expression of TLR4/MyD88/NF-κB with Insulin Resistance in Placentae of Gestational Diabetes Mellitus

Insulin resistance (IR) is a critical factor of the pathophysiology of Gestational diabetes mellitus (GDM). Studies on key organs involved in IR, such as livers and adipose tissues, showed that Toll-like receptor 4 (TLR4) can regulate insulin sensitivity. As a maternal-fetal interface with multi-functions, placentae could contribute to the development of IR for GDM. Thus, we investigated the expressions of TLR4/Myeloid Differentiation factor 88 (MyD88)/Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-kB) in term placentae from 33 GDM women and 36 healthy pregnant women with normal glucose tolerance, evaluated local and systemic IR and furthermore identified the association between placental TLR4 and IR. TLR4 protein was expressed in various cells of term placenta, particularly in syncytiotrophoblast of villi. Compared with normal pregnancy, the expression of TLR4/MyD88/NF-kB pathway increased in the placenta of GDM (p<0.05), and these differences were more pronounced in the maternal section of the placenta and the syncytiotrophoblast of villi. In addition, more severe IR was observed in the placenta of GDM patients than the control group, evidenced with higher pIRS-1(ser312) (p<0.001) and lower IRS-1 (p<0.05) as well as pAkt proteins (p<0.01). The expression of TLR4 in placentae is positively correlated with local IR (pIRS-1: r = 0.76, p <0.001 and pAkt: r = -0.47, p <0.001) and maternal fasting (r = 0.42, p <0.01), one-hour (r = 0.52, p <0.01) and two-hour glucose (r = 0.54, p <0.01) at OGTT. We found an that enhanced expression of the TLR4-MyD88-NF-kB pathway occurs in GDM placentae, which positively correlates with heightened local IR in placentae and higher maternal hyperglycemia. The TLR4/MyD88/NF-kB pathway may play a potential role in the development of IR in placentae of 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.

Adiponectin, C-reactive protein, fibrinogen and tissue plasminogen activator antigen levels among glucose-intolerant women with and without histories of gestational diabetes

AIM

To examine concentrations of biomarkers (adiponectin, C-reactive protein, fibrinogen and tissue plasminogen-activator antigen) associated with glucose homeostasis and diabetes risk by history of gestational diabetes (GDM).

METHODS

We conducted a secondary analysis of the Diabetes Prevention Program, a randomized trial of lifestyle intervention or metformin for diabetes prevention. At baseline, participants were overweight and had impaired glucose tolerance. Biomarkers at baseline and 1 year after enrolment were compared between parous women with (n = 350) and without histories of GDM (n = 1466). Cox proportional hazard models evaluated whether history of GDM was associated with diabetes risk, after adjustment for baseline biomarker levels as well as for change in biomarker levels, demographic factors and anthropometrics.

RESULTS

At baseline, women with histories of GDM had lower adiponectin (7.5 μg/ml vs. 8.7 μg/ml; p < 0.0001) and greater log C-reactive protein (-0.90 mg/l vs. -0.78 mg/l, p = 0.04) levels than women without histories of GDM, but these associations did not persist after adjustment for demographic factors. Fibrinogen and tissue plasminogen-activator antigen were similar between women with and without histories of GDM. Women with and without histories of GDM had a similar pattern of changes in biomarkers within randomization arm. Adjustment for age, race/ethnicity, baseline weight, change in weight, baseline biomarker level and change in biomarker level did not significantly alter the association between history of GDM, and diabetes risk.

CONCLUSIONS

Among women with impaired glucose tolerance, biomarkers in women with and without histories of GDM are similar and respond similarly to lifestyle changes and metformin. Adjustment for biomarker levels did not explain the higher risk of diabetes observed in women with histories of GDM.

Association of oxidative stress biomarkers with gestational diabetes mellitus in pregnant women: a case-control study

Objective

The relationship between gestational diabetes mellitus (GDM) and oxidative stress has not been fully elucidated. This study examined the association between biomarkers of oxidative stress and GDM.

Methods

We conducted a case-control study which included 36 women presenting with GDM and 36 asymptomatic matched control subjects who visited Guangzhou Women and Children’s Medical Centre, China, from June 2012 to December 2012. Pregnant women were prospectively recruited to the study, and blood samples were collected at the time of a routine oral glucose tolerance test. These samples were then analyzed for levels of endocrine and surrogate markers of oxidative stress.

Results

Compared to control subjects, women with GDM exhibited elevated values for plasma glucose, insulin, and insulin resistance (IR), and showed reduced HOMA pancreatic β-cell function (HOMA-B), insulin sensitivity index (ISI), insulinogenic index, and corrected insulin response at 24–28 weeks gestation. A bivariate logistic regression analysis showed that levels of high-sensitivity C reactive protein (hs-CRP) and high fluorescence reticulocytes at fasting, and hs-CRP in a 1-h OGTT, were significantly associated with GDM. A linear regression analysis showed that levels of hs-CRP (P = 0.003) and reticulocytes (P = 0.029) at fasting were associated with IR, and levels of hs-CRP (P = 0.002) and monocytes (P = 0.006) in a 1-h OGTT were associated with ISI.

Conclusions

Pregnant women with GDM developed a pathological IR and exhibited β-cell dysfunction. Their decreased ability to compensate for oxidative stress was associated with increased IR and a reduced ISI, which might be important factors in GDM.

Asymmetric dimethylarginine is associated with high-sensitivity C-reactive protein and early carotid atherosclerosis in women with previous gestational diabetes mellitus

Asymmetric dimethylarginine (ADMA) is increased in subjects with previous gestational diabetes mellitus (GDM). The aim of this study was to investigate the relationship between serum ADMA levels and early carotid atherosclerosis in women with history of GDM. A total of 42 normoglycemic women with previous GDM and 42 age-matched healthy controls were enrolled. Serum levels of ADMA, lipids, insulin, fasting and 2-h glucose following 75-g oral glucose tolerance test, and high sensitivity C-reactive protein (hsCRP) were measured. Carotid atherosclerosis was evaluated by ultrasonographically determined intima-media thickness (IMT). Serum ADMA and hsCRP were higher in women with previous GDM compared to the healthy controls (0.72 ± 0.16 vs. 0.41 ± 0.15 μmol/L, p < 0.001; 1.81 ± 0.32 vs. 1.05 ± 0.26 mg/L, p < 0.001; respectively). Carotid IMT was also increased in the previous GDM group (0.77 ± 0.14 vs. 0.52 ± 0.13 mm, p < 0.001). In women with previous GDM, ADMA was positively correlated with hsCRP (r = 41, p < 0.001) and carotid IMT (r = 0.38, p < 0.001). Multiple linear regression analysis revealed that ADMA was a significant predictor for elevated carotid IMT in subjects with previous GDM after adjusting for traditional risk factors (β = 0.26, p = 0.017). Our data demonstrated that serum ADMA was associated with hsCRP and carotid IMT in normoglycemic women with previous GDM.

Plasma levels and placental expression of vaspin in pregnant women with diabetes mellitus

The present study aimed to investigate visceral adipose tissue-specific serpin (vaspin) concentrations in serum and term placentas and relate these values to insulin resistance and lipid parameters in women with gestational diabetes mellitus (GDM). A total of 30 GDM subjects and 27 age-matched pregnant women with normal glucose tolerance (NGT, control) were included. Serum glucose, glycated hemoglobin (HbA1c), lipid profile, insulin, and vaspin were measured at the end of pregnancy, and homeostasis model of assessment-insulin resistance (HOMA-IR) values were calculated. Vaspin mRNA and protein levels in placentas were measured by real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blotting, respectively. Serum vaspin levels were significantly lower in the GDM group than in controls (0.49±0.24 vs 0.83±0.27 ng/mL, respectively; P<0.01). Three days after delivery, serum vaspin levels were significantly decreased in subjects with GDM (0.36±0.13 vs 0.49±0.24 ng/mL, P<0.01). However, in the GDM group, serum vaspin levels were not correlated with the parameters evaluated. In contrast, in the control group, serum vaspin levels were positively correlated with triglycerides (TG; r=0.45, P=0.02) and very low-density lipoprotein cholesterol (VLDL-C; r=0.42, P=0.03). Placental mRNA vaspin (0.60±0.32 vs 0.68±0.32, P=0.46) and protein (0.30±0.08 vs 0.39±0.26; P=0.33) levels in the GDM group did not differ significantly from those in the control group, but were negatively correlated with neonatal birth weight in the GDM group (r=-0.48, P=0.03; r=-0.88; P<0.01). Our findings indicated that vaspin may be an important adipokine involved in carbohydrate and lipid metabolism and may also play a role in fetal development.

The first trimester: prediction and prevention of the great obstetrical syndromes

A number of groups are currently examining the potential of screening for pre-eclampsia and gestational diabetes at 12 weeks' gestation. This can be performed at the time of combined first-trimester screening for aneuploidy using a similar method of regression analysis to combine multiple demographic and investigative factors. At present, research into the prediction of pre-eclampsia is more robust and is associated with the potential for therapeutic intervention that can reduce the prevalence of early-onset pre-eclampsia and improve maternal and neonatal outcomes.

Simple lifestyle recommendations and the outcomes of gestational diabetes. A 2 × 2 factorial randomized trial

The benefits of exercise and behavioural recommendations in gestational diabetes mellitus (GDM) are controversial. In a randomized trial with a 2 × 2 factorial design, we examined the effect of exercise and behavioural recommendations on metabolic variables, and maternal/neonatal outcomes in 200 GDM patients. All women were given the same diet: group D received dietary recommendations only; group E was advised to briskly walk 20-min/day; group B received behavioural dietary recommendations; group BE was prescribed the same as B + E. Dietary habits improved in all groups. In a multivariable regression model, fasting glucose did not change. Exercise, but not behavioural recommendations, was associated with the reduction of postprandial glucose (p < 0001), glycated haemoglobin (HbA1c; p < 0.001), triglycerides (p = 0.02) and C-reactive protein (CRP; p < 0.001) and reduced any maternal/neonatal complications (OR = 0.50; 95%CI=0.28-0.89;p = 0.02). In GDM patients a simple exercise programme reduced maternal postprandial glucose, HbA1c, CRP, triglycerides and any maternal/neonatal complications, but not fasting glucose values.

Total adiponectin, but not inflammatory markers C-reactive protein, tumor necrosis factor-α, interluekin-6 and monocyte chemoattractant protein-1, correlates with increasing glucose intolerance in pregnant Chinese-Americans

BACKGROUND

Elevated insulin, C-reactive protein (CRP), tumor necrosis factor (TNF)-α, interleukin (IL)-6, and monocyte chemoattractant protein (MCP)-1 levels and decreased high molecular weight adiponectin (HMW-APN) levels have been reported in Caucasians with gestational diabetes mellitus (GDM). No similar studies have been performed in Chinese women.

METHODS

Serum samples were obtained 1 h after a 50-g glucose challenge test (1HGCT) from Chinese-American women at 24-28 gestational weeks and total adiponectin (T-APN), HMW-APN, CRP, TNF-α, IL-6, and MCP-1 concentrations were measured. Correlation coefficients for glucose (1HGCT), HbA1c, insulin, and body mass index (BMI) were calculated against T-APN, HMW-APN, CRP, TNF-α, IL-6, and MCP-1. Significant P-values were determined using Bonferroni adjustments.

RESULTS

Women with GDM had higher insulin and 1HGCT and lower T-APN. In addition, T-APN was lower in non-GDM subjects who had 1HGCT ≥135 mg/dL with no abnormal or one abnormal glucose value on the 3-h oral glucose tolerance test. There were no significant differences in HMW-APN and inflammatory marker levels between non-GDM and GDM groups. There were negative correlations between T-APN and 1HGCT, insulin, BMI, and HbA1c, as well as between HMW-APN and 1HGCT, insulin, and BMI. No significant correlations were observed between 1HGCT, HbA1c, insulin, or BMI and CRP, TNF-α, IL-6, or MCP-1.

CONCLUSIONS

T-APN is reduced in Chinese women with GDM and those without GDM but with evidence of glucose intolerance. Unlike results reported for Caucasians, Chinese-American women with GDM do not exhibit elevated levels of CRP, TNF-α, IL-6, or MCP-1, possibly because Chinese women are relatively leaner compared with Caucasians.

Comparative study between different biomarkers for early prediction of gestational diabetes mellitus

OBJECTIVE

To study various biomarkers in prediction of gestational diabetes mellitus (GDM).

PATIENTS AND METHODS

Prospective observational study included 400 pregnant women. Maternal serum sex hormone binding globulin (SHBG), high-sensitive C-reactive protein (hs-CRP), uric acid, creatinine and albumin were measured before 15 weeks of gestation. Patients were followed-up for development of GDM.

RESULTS

A total of 269 women were eligible for analysis. GDM complicated 27 (10.03%) of pregnancies. Hs-CRP levels were significantly higher and SHBG levels were significantly lower among women who subsequently developed GDM compared with normoglycemics. Uric acid, albumin and creatinine levels were not significantly different between both groups. For prediction of GDM, hs-CRP at a cutoff value of 2.55 mg/l showed a sensitivity and a specificity of 89% and 55%, respectively. SHBG at a cutoff value of 211.5 nmol/l showed a sensitivity and a specificity of 85% and 37%, respectively. Low SHBG with high hs-CRP predicted GDM with a sensitivity and specificity of 74.07% and 75.62%, respectively with an overall accuracy of 75.46%.

CONCLUSION

Hs-CRP and SHBG are important early predictors of GDM. Adding SHBG to hs-CRP improves specificity and serves good overall accuracy. Uric acid, creatinine and albumin have no role in GDM prediction.

Perinatal depression--the fourth inflammatory morbidity of pregnancy?: Theory and literature review

Perinatal depression is one of the leading causes of maternal morbidity and mortality. The biological etiology of this disorder remains in question, despite considerable research into the contributions of hormonal imbalance, the role of monoamines, and dysregulation of the HPA axis. Because inflammation is known to be associated with major depression in men and non-perinatal women as well as with other important morbidities of pregnancy (such as preeclampsia, preterm birth, and gestational diabetes), and because these morbidities may correlate with perinatal depression, inflammation may be a common physiological pathway that can also help explain perinatal depression. In this paper, we review the theoretical background of inflammation in perinatal depression and then review the literature concerning immune and inflammatory factors in the etiology and course of perinatal depression. We close with recommendations for future studies in this still relatively unexplored area. Identification and understanding of a common pathophysiology between other pregnancy morbidities and perinatal depression would link physical and mental well-being, likely leading to better treatment and prevention.

Association between adiponectin and tumor necrosis factor-alpha levels at eight to fourteen weeks gestation and maternal glucose tolerance: the Parity, Inflammation, and Diabetes Study

OBJECTIVE

Inflammation may influence gestational hyperglycemia, but to date, the data from observational studies is largely limited to results from the third trimester of pregnancy. Our objective was to evaluate first trimester adipocytokine levels. We sought to determine whether first trimester adiponectin and tumor necrosis factor-alpha (TNF)-alpha concentrations were independently associated and predictive of maternal glucose tolerance, as measured by the 1-hour glucose challenge test (GCT), after adjustment for maternal lifestyle behaviors and body mass index (BMI).

MATERIAL AND METHODS

Prospective study of pregnant women (n=211) enrolled in the Parity, Inflammation, and Diabetes Study. Nonfasting serum levels of adiponectin and TNF-r2 were measured at 8-14 weeks of pregnancy. GCT results were abstracted from electronic prenatal records. Multiple linear regression models were developed to determine the association of adiponectin and TNF-r2 levels with response to the GCT, adjusting for demographics, pregravid dietary intake and physical activity, first trimester BMI, and gestational weight gain.

RESULTS

At baseline, higher adiponectin concentrations were inversely and statistically significantly associated with maternal response to the GCT [regression coefficient (β) -0.68; 95% confidence interval (CI): -1.29, -0.06). Adjustment for lifestyle factors did not alter the association of adiponectin with the GCT (β -0.74; 95% CI: -1.43, -0.05). After adjustment for first trimester BMI, the association of adiponectin was attenuated and no longer significant (β -0.46; 95% CI: -1.15, 0.24). TNF-r2 levels were not associated with the GCT (β -0.003; 95% CI: -0.011, 0.005).

CONCLUSIONS

First trimester adiponectin levels are not predictive of the 1-hour GCT response, but may be a marker for the effect of maternal BMI on glucose response to the GCT.

Cytokine levels in gestational diabetes mellitus: a systematic review of the literature

PROBLEM

Gestational diabetes mellitus (GDM) is an inflammatory condition that involves unbalanced cytokine production. We carried out a systematic review on the relationship between GDM and maternal circulating levels of cytokines in the 2nd/3rd trimesters.

METHOD OF STUDY

Three electronic databases (MEDLINE, EMBASE and LILACS), were searched. Duplicate study selection, extraction and quality assessment was performed.

RESULTS

Twenty-two studies with 1982 participants reporting levels of 9 cytokines (IL-1B, IL-2, IL-6, IL-10, IL-13, IL-18, IFN-G, TGF-B and TNF-A) were included. Most studies differed considerably in selection criteria, sampling and assay methods and in reporting their results. Consequently, only two studies could be pooled: TNF-A concentration was slightly higher in GDM than in control patients, although not significant (WMD=0.45, 95% CI -0.34-1.23).

CONCLUSIONS

New studies with well-defined, more homogeneous methodological parameters are needed to detect whether there are significant differences in circulating levels of cytokines in patients with GDM.

The role of inflammatory pathway genetic variation on maternal metabolic phenotypes during pregnancy

Background

Since mediators of inflammation are associated with insulin resistance, and the risk of developing diabetes mellitus and gestational diabetes, we hypothesized that genetic variation in members of the inflammatory gene pathway impact glucose levels and related phenotypes in pregnancy. We evaluated this hypothesis by testing for association between genetic variants in 31 inflammatory pathway genes in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) cohort, a large multiethnic multicenter study designed to address the impact of glycemia less than overt diabetes on pregnancy outcome.

Results

Fasting, 1-hour, and 2-hour glucose, fasting and 1-hour C-peptide, and HbA1c levels were measured in blood samples obtained from HAPO participants during an oral glucose tolerance test at 24-32 weeks gestation. We tested for association between 458 SNPs mapping to 31 genes in the inflammatory pathway and metabolic phenotypes in 3836 European ancestry and 1713 Thai pregnant women. The strongest evidence for association was observed with TNF alpha and HbA1c (rs1052248; 0.04% increase per allele C; p-value = 4.4×10⁻⁵), RETN and fasting plasma glucose (rs1423096; 0.7 mg/dl decrease per allele A; p-value = 1.1×10⁻⁴), IL8 and 1 hr plasma glucose (rs2886920; 2.6 mg/dl decrease per allele T; p-value = 1.3×10⁻⁴), ADIPOR2 and fasting C-peptide (rs2041139; 0.55 ug/L decrease per allele A; p-value = 1.4×10⁻⁴), LEPR and 1-hour C-peptide (rs1171278; 0.62 ug/L decrease per allele T; p-value = 2.4×10⁻⁴), and IL6 and 1-hour plasma glucose (rs6954897; −2.29 mg/dl decrease per allele G, p-value = 4.3×10⁻⁴).

Conclusions

Based on the genes surveyed in this study the inflammatory pathway is unlikely to have a strong impact on maternal metabolic phenotypes in pregnancy although variation in individual members of the pathway (e.g. RETN, IL8, ADIPOR2, LEPR, IL6, and TNF alpha,) may contribute to metabolic phenotypes in pregnant women.

Role of adipokines and other inflammatory mediators in gestational diabetes mellitus and previous gestational diabetes mellitus

Previous Gestational Diabetes Mellitus (pGDM) is a common condition and has been associated with future development of Type 2 Diabetes Mellitus (T2DM) and Metabolic Syndrome (MS) in women affected. The pathogenesis and risk factors implicated in the development of these conditions later in the lives of women with pGDM are not as yet fully understood. Research has recently focused on a group of substances produced mainly by adipose tissue called adipokines, this group including, among others, adiponectin, leptin, Retinol-Binding Protein-4 (RBP-4), and resistin. These substances as well as other inflammatory mediators (CRP, IL-6, PAI-1, TNF-α) seem to play an important role in glucose tolerance and insulin sensitivity dysregulation in women with pGDM. We summarize the data available on the role of these molecules.

Inflammatory mediators and glucose in pregnancy: results from a subset of the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study

CONTEXT

Inflammatory mediators are associated with type 2 and gestational diabetes. It is unknown whether there are associations with glucose in pregnant women with lesser degrees of hyperglycemia.

OBJECTIVE

The objective of the study was to examine associations of inflammatory mediators with maternal glucose levels and neonatal size in a subset of participants in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study.

DESIGN

Eligible pregnant women underwent a 75-g oral glucose tolerance test between 24 and 32 wk gestation, and levels of C-peptide, adiponectin, plasminogen activator inhibitor type 1 (PAI-1), C-reactive protein (CRP), and resistin were measured in fasting serum samples. Associations of inflammatory mediators with maternal glucose and with birth size were assessed using multiple linear regression analyses, adjusting for maternal body mass index (BMI), fasting C-peptide, and other potential confounders.

RESULTS

Mean levels of adiponectin declined, and PAI-1 and CRP increased across increasing levels of maternal glucose, BMI, and C-peptide. For example, for fasting plasma glucose less than 75 mg/dl and fasting plasma glucose of 90 mg/dl or greater, adiponectin was 22.5 and 17.4 μg/ml and PAI-1 was 30.9 and 34.2 ng/ml, respectively. Associations with 1- and 2-h plasma glucose remained significant for adiponectin (P<0.001), PAI-1 (P<0.05), and CRP (P<0.01) after adjustment for BMI and C-peptide. Adiponectin and CRP were inversely associated with birth weight, sum of skinfolds and percent body fat, and PAI-1 with sum of skinfolds (all P<0.05) after adjustment for confounders. Resistin was not associated with 1- or 2-h glucose or birth size.

CONCLUSION

Levels of inflammatory mediators are associated with levels of maternal glucose in pregnant women without overt diabetes.

Increased serum retinol-binding protein-4 levels in pregnant women with and without gestational diabetes mellitus

OBJECTIVE

Retinol-binding protein 4 (RBP4) is thought to be associated with insulin resistance in humans, while pregnancy is normally characterized by progressive insulin resistance. Gestational diabetes (GDM) occurs when pancreatic beta-cell function is unable to compensate for insulin resistance. This study aimed to determine whether or not serum RBP4 levels are elevated in pregnancy, and to explore the relationship between RBP4 levels and insulin resistance during pregnancy.

METHODS

Serum RBP4 was measured at median gestational week 26 in 121 pregnant women, including 63 with GDM (GDM group) and 58 normal, glucose-tolerant pregnant women (P-NGT group), as well as 65 non-pregnant normal, glucose-tolerant women (NP-NGT group). Multiple stepwise regression analysis was used to explore the independent factors of RBP4.

RESULTS

Serum RBP4 levels in the P-NGT and GDM groups were significantly higher than in the NP-NGT group (34.50±9.80 mg/L and 41.64±12.21 mg/L vs 30.64±9.46 mg/L, respectively; P<0.05) after adjusting for age, body mass index (BMI) and blood pressure. Furthermore, RBP4 levels were much higher in the GDM vs P-NGT group. Spearman's correlation analysis showed that serum RBP4 levels were positively correlated with triglycerides (TG), fasting plasma glucose, postprandial 2h plasma glucose and HOMA-IR in pregnancy. Of these, TG and HOMA-IR (r(2)=0.312) were independent factors of serum RBP4.

CONCLUSION

Serum RBP4 levels are significantly increased in pregnancy, independent of age and BMI, and are also considerably higher in pregnant women with GDM than in those with normal glucose tolerance. In addition, serum RBP4 levels appear to be a valuable marker of insulin resistance and dysfunctional lipid metabolism in pregnancy.

YKL-40 concentrations are not elevated in gestational diabetes

BACKGROUND

Gestational diabetes (GDM) is an increasing and common complication of pregnancy. The involvement of inflammatory mechanisms in GDM remains unclear. YKL-40 is a novel inflammatory marker that has been recently found to be associated with type 2 diabetes. This is the first study to investigate YKL-40 in GDM.

MATERIAL AND METHODS

A total of 58 subjects were included, 28 patients with GDM (BMI 33.2 +/- 6.1 kg m(-(2)), 33 +/- 6 years) and 30 healthy pregnant controls (BMI 28.4 +/- 5.2 kg m(-(2)), 33 +/- 4 years; mean +/- SD). Standard risk factors for GDM (weight and BMI prior to pregnancy, family history, former GDM, high birthweight offspring) were evaluated. A 2-h 75-g oral glucose tolerance test (oGTT) and measurement of YKL-40 were conducted in gestational week 28 +/- 4, as well as 8 weeks after delivery.

RESULTS

YKL-40 was not different between GDM and controls, neither during (65.8 +/- 44.4 vs. 60.3 +/- 30.1 ng mL(-1)), nor after pregnancy (63.4 +/- 30.5 vs. 66.9 +/- 32.7 ng mL(-1)). YKL-40 was correlated with insulin, HOMA and BMI. GDM had higher fasting insulin (14.1 +/- 7.4 vs. 8.3 +/- 4.3 muU mL(-1)) and glucose (88 +/- 13 - 200 +/- 31 - 160 +/- 33 vs. 76 +/- 10 - 146 +/- 37 - 112 +/- 28 mg dL(-1) for fasting, 1- and 2-h-concentrations in the oGTT, respectively), higher HbA1c (5.3 +/- 0.4 vs. 5.0 +/- 0.5%;), HOMA (3.1 +/- 1.7 vs. 1.6 +/- 0.9), and BMI (33.2 +/- 6.1 vs. 28.5 +/- 5.2 kg m(-2)) (means +/- SD, all P < 0.01).

CONCLUSIONS

No difference in YKL-40 between GDM and controls suggests similar inflammatory status at the time of measurements. The short duration of metabolic changes during GDM might explain this finding, which is in contrast to results in type 2 diabetes.

Maternal obesity and markers of inflammation in pregnancy

OBJECTIVES

To evaluate whether obesity is associated with changes in pro-inflammatory and immunomodulatory cytokines in pregnancy.

METHODS

We performed a cross-sectional study using maternal serum from the early second trimester to examine biomarkers associated with inflammation in relation to maternal body mass index (n=80 total).

RESULTS

Leptin and high sensitivity C-reactive protein were significantly different between groups and increased with increasing body mass index. MCP-1 was significantly increased in the morbidly obese mothers. Interleukin-2 exhibited a U-shaped relationship with body mass index; transforming growth factor-beta1 demonstrated a nonsignificant negative trend with body mass index; and the levels of hepatocyte growth factor and tumor necrosis factor-alpha did not differ appreciably between groups.

CONCLUSIONS

Maternal obesity in pregnancy is associated with changes in cytokines, protein hormones and acute phase proteins in the second trimester, with an increase in MCP-1 in the morbid obesity category, and an increase in Leptin and hsCRP with increasing BMI category.

Maternal visfatin concentration in normal pregnancy

OBJECTIVE

Adipose tissue has now emerged as a powerful endocrine organ via the production of adipokines. Visfatin, a novel adipokine with diabetogenic and immuno-modulatory properties has been implicated in the pathophysiology of insulin resistance in patients with obesity and Type-2 diabetes mellitus. The aim of this study was to determine whether there are changes in the maternal plasma concentration of visfatin with advancing gestation and as a function of maternal weight.

STUDY DESIGN

In this cross-sectional study, maternal plasma concentrations of visfatin were determined in normal weight and overweight/obese pregnant women in the following gestational age groups: 1) 11-14 weeks (n=52); 2) 19-26 weeks (n=68); 3) 27-34 weeks (n=93); and 4) >37 weeks (n=60). Visfatin concentrations were determined by ELISA. Non parametric statistics were used for analysis.

RESULTS

1) The median maternal plasma visfatin concentration was higher in pregnant women between 19-26 weeks of gestation than that of those between 11-14 weeks of gestation (P<0.01) and those between 27-34 weeks of gestation (P<0.01); 2) among normal weight pregnant women, the median plasma visfatin concentrations of women between 19-26 weeks of gestation was higher than that of those between 11-14 weeks (P<0.01) and those between 27-34 weeks (P<0.01); and 3) among overweight/obese patients, the median maternal visfatin concentration was similar between the different gestational age groups.

CONCLUSION

The median maternal plasma concentration of visfatin peaks between 19-26 and has a nadir between 27-34 weeks of gestation. Normal and overweight/obese pregnant women differed in the pattern of changes in circulating visfatin concentrations as a function of gestational age.

Serum concentrations of retinol-binding protein 4 in women with and without gestational diabetes

AIMS/HYPOTHESIS

Pregnancy is characterised by temporarily increased insulin resistance. Gestational diabetes occurs when pancreatic beta cell function is unable to compensate for this insulin resistance. Retinol-binding protein 4 (RBP4) could be related to insulin resistance. We hypothesised that RBP4 is elevated in gestational diabetes.

METHODS

Serum RBP4, transthyretin and retinol were cross-sectionally measured in 42 women with gestational diabetes and 45 pregnant controls. Of these, 20 women with and 22 without gestational diabetes were included in an additional longitudinal study. RBP4 was determined by enzyme immunometric assay (EIA) and western blot.

RESULTS

Women with gestational diabetes had lower RBP4 EIA and western blot levels than controls (median 6.8 [interquartile range, 3.9-14.3] vs 11.3 [7.8-19.9] microg/ml, p < 0.001 and 25.1 [21.7-29.6] vs 26.6 [23.5-32.2] microg/ml, p = 0.026). Transthyretin and the RBP4:transthyretin molar ratio were comparable between the groups. Serum retinol was lower (p < 0.001) and the RBP4 Western blot level: retinol molar ratio was higher in women with gestational diabetes (p = 0.044). RBP4 was not associated with the glucose or homeostasis model assessment of insulin resistance (HOMA-IR), but in gestational diabetes the RBP4:retinol molar ratio correlated with blood glucose and negatively with 2 h post-load insulin. The RBP4:transthyretin ratio correlated with HOMA-IR and fasting insulin in controls. In women with gestational diabetes RBP4 EIA and western blot levels increased after delivery. Retinol increased in both groups, while transthyretin and the RBP4:transthyretin ratio were not altered after parturition.

CONCLUSIONS/INTERPRETATION

RBP4 measured by two different techniques is not elevated, but the RBP4:retinol molar ratio is higher and correlates with fasting blood glucose in women with gestational diabetes. Thus, the RBP4:retinol ratio and the RBP4:transthyretin ratio are more informative than RBP4 levels alone when assessing insulin-glucose homeostasis during pregnancy.

Serum concentrations of retinol-binding protein 4 in women with and without gestational diabetes

AIMS/HYPOTHESIS

Pregnancy is characterised by temporarily increased insulin resistance. Gestational diabetes occurs when pancreatic beta cell function is unable to compensate for this insulin resistance. Retinol-binding protein 4 (RBP4) could be related to insulin resistance. We hypothesised that RBP4 is elevated in gestational diabetes.

METHODS

Serum RBP4, transthyretin and retinol were cross-sectionally measured in 42 women with gestational diabetes and 45 pregnant controls. Of these, 20 women with and 22 without gestational diabetes were included in an additional longitudinal study. RBP4 was determined by enzyme immunometric assay (EIA) and western blot.

RESULTS

Women with gestational diabetes had lower RBP4 EIA and western blot levels than controls (median 6.8 [interquartile range, 3.9-14.3] vs 11.3 [7.8-19.9] microg/ml, p < 0.001 and 25.1 [21.7-29.6] vs 26.6 [23.5-32.2] microg/ml, p = 0.026). Transthyretin and the RBP4:transthyretin molar ratio were comparable between the groups. Serum retinol was lower (p < 0.001) and the RBP4 Western blot level: retinol molar ratio was higher in women with gestational diabetes (p = 0.044). RBP4 was not associated with the glucose or homeostasis model assessment of insulin resistance (HOMA-IR), but in gestational diabetes the RBP4:retinol molar ratio correlated with blood glucose and negatively with 2 h post-load insulin. The RBP4:transthyretin ratio correlated with HOMA-IR and fasting insulin in controls. In women with gestational diabetes RBP4 EIA and western blot levels increased after delivery. Retinol increased in both groups, while transthyretin and the RBP4:transthyretin ratio were not altered after parturition.

CONCLUSIONS/INTERPRETATION

RBP4 measured by two different techniques is not elevated, but the RBP4:retinol molar ratio is higher and correlates with fasting blood glucose in women with gestational diabetes. Thus, the RBP4:retinol ratio and the RBP4:transthyretin ratio are more informative than RBP4 levels alone when assessing insulin-glucose homeostasis during pregnancy.

Gestational diabetes, inflammation, and late vascular disease

Physiological changes of pregnancy include insulin resistance and activation of the innate immunity with an inflammatory response. The working hypothesis is that the sub-clinical inflammation associated with excessive adiposity may favor the development of gestational diabetes (GDM) and Type 2 diabetes and other metabolic abnormalities related to cardiovascular disease later in life. In this paper we review the complex interrelationship among inflammatory markers, metabolic syndrome, and endothelium dysfunction in women with GDM and discuss if women with previous GDM (pGDM) could be considered at risk for cardiovascular diseases. MEDLINE was searched for articles relating GDM and the adipokines (tumor necrosis factor-alpha and adiponectin) as well as the acute-phase inflammatory biomarker C-reactive protein that contribute to the development of diabetic pregnancy and vascular complications. However, to date, in pGDM women no prospective study is available, to corroborate the hypothesis that inflammatory pattern could be taken as predictor of cardiovascular disease later in life. Therefore, our paper should provide arguments to perform follow-up programs to prevent cardiovascular events in women with pGDM. Control of body weight, regular physical exercise are indeed powerful intervention tools able at improving insulin sensitivity and reduce sub-clinical inflammation, both involved in the pathogenesis of cardiovascular disease.

Insulin resistance has no impact on ghrelin suppression in pregnancy

Ghrelin is reduced in various states of insulin resistance. The aim of this study was to examine the relationship between ghrelin and glucose metabolism during pregnancy - a natural insulin-resistant state - in women with normal glucose tolerance (NGT), impaired glucose tolerance (IGT) or gestational diabetes mellitus (GDM) and potential changes 3 months after delivery. A total of 54 women, 37 pregnant and with various degrees of insulin resistance and 24 postpartum (PP, seven of them also studied during pregnancy) were studied. Ghrelin plasma concentrations at fasting and 60' following glucose loading (75 g-2 h-oral glucose tolerance test), area under the curve of plasma glucose (G-AUC(OGTT)) and insulin sensitivity [homeostatic model assessment (HOMA) and oral glucose sensitivity index (OGIS) indices, respectively] were determined. Both baseline and 60' ghrelin concentrations were to a comparable degree ( approximately by 65%) suppressed in NGT, IGT and GDM as compared to the PP group (the latter being indistinguishable from NGT regarding glucose tolerance and insulin sensitivity). In all women studied both during and after pregnancy, ghrelin levels rose from pregnancy to PP (mean increase 313.8%; P < 0.03). There was no correlation between baseline ghrelin and insulin sensitivity as estimated from both baseline (HOMA) and dynamic (OGTT:OGIS) glucose and insulin data. Ghrelin is substantially decreased during pregnancy, but glucose-induced ghrelin suppression is preserved at a lower level. There is apparently no relation to the degree of insulin resistance.

Elevated concentrations of asymmetric dimethylarginine are associated with deterioration of glucose tolerance in women with previous gestational diabetes mellitus

OBJECTIVE

Women with previous gestational diabetes mellitus (GDM) have a high risk for development of type 2 diabetes mellitus. The endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine (ADMA) could be related to disorders of the glucose metabolism. To evaluate if ADMA predicts deterioration of glucose tolerance in women with previous GDM and to assess concentration changes we analysed ADMA in women with previous GDM after delivery and after a median follow-up of 2.75 years (interquartile range: 1.47-4.60).

DESIGN

Prospective cohort study. Subjects and methods. ADMA, symmetric dimethylarginine (SDMA) and L-arginine were determined in 77 women with previous GDM who underwent a 75-g oral glucose tolerance test 4 months after delivery and at follow-up.

RESULTS

Deterioration in glucose tolerance was observed in 36% of the women with ADMA above and 11% of those with ADMA below the median (0.56 micromol L(-1); P = 0.008, log-rank test). ADMA correlated significantly with mean arterial blood pressure and nonsignificantly with body mass index (P = 0.050) but not with insulin resistance, fasting glucose, lipids or glomerular filtration rate. The fully adjusted hazard ratio for a decline of glucose tolerance during follow-up was 3.94 (95% CI: 1.16-13.37; P = 0.028) for subjects with ADMA above the median. SDMA and L-arginine were not associated with changes in the glucose tolerance status. ADMA and L-arginine decreased significantly during follow-up.

CONCLUSIONS

High serum ADMA after delivery is associated with deterioration in glucose tolerance in women with previous GDM and declines in the following years.

A prospective study of dietary patterns, meat intake and the risk of gestational diabetes mellitus

AIMS/HYPOTHESIS

The aim of this study was to prospectively examine whether dietary patterns are related to risk of gestational diabetes mellitus (GDM).

METHODS

This prospective cohort study included 13,110 women who were free of cardiovascular disease, cancer, type 2 diabetes and history of GDM. Subjects completed a validated semi-quantitative food frequency questionnaire in 1991, and reported at least one singleton pregnancy between 1992 and 1998 in the Nurses' Health Study II. Two major dietary patterns (i.e. 'prudent' and 'Western') were identified through factor analysis. The prudent pattern was characterised by a high intake of fruit, green leafy vegetables, poultry and fish, whereas the Western pattern was characterised by high intake of red meat, processed meat, refined grain products, sweets, French fries and pizza.

RESULTS

We documented 758 incident cases of GDM. After adjustment for age, parity, pre-pregnancy BMI and other covariates, the relative risk (RR) of GDM, comparing the highest with the lowest quintile of the Western pattern scores, was 1.63 (95% CI 1.20-2.21; p (trend)=0.001), whereas the RR comparing the lowest with the highest quintile of the prudent pattern scores was 1.39 (95% CI 1.08-1.80; p (trend)=0.018). The RR for each increment of one serving/day was 1.61 (95% CI 1.25-2.07) for red meat and 1.64 (95% CI 1.13-2.38) for processed meat.

CONCLUSIONS/INTERPRETATION

These findings suggest that pre-pregnancy dietary patterns may affect women's risk of developing GDM. A diet high in red and processed meat was associated with a significantly elevated risk.