Circulating levels of the antiangiogenic marker soluble FMS-like tyrosine kinase 1 are elevated in women with pregestational diabetes and preeclampsia: angiogenic markers in preeclampsia and preexisting diabetes

Placental expression of endoglin, placental growth factor, leptin, and hypoxia-inducible factor-1 in diabetic pregnancy and pre-eclampsia

OBJECTIVE

To evaluate a level of expression of endoglin (Eng), leptin (Lep), placental growth factor (PlGF), and hypoxia-inducible factor-1alpha (HIF-1α) in placenta among women with pre-eclampsia and diabetes mellitus (DM), considering the method of glycemia correction and preconception care.

MATERIALS AND METHODS

A retrospective cohort study was conducted. A total of 124 women were divided into following groups: type 1 DM (n = 40), type 2DM (n = 31), gestational DM (n = 33), pre-eclampsia without DM (PE) (n = 10) and the control group (n = 10). The histochemical study was performed by using primary monoclonal antibodies to Eng, PlGF, Lep, and HIF-1α (Abcam, UK).

RESULTS

The highest level of placental expression of Eng was observed in the PE group (20.34%). The same trend was also typical for T1DM (not planned) and insulin-treated groups: T2DM and GDM. An amount of cell with an PlGF expression was significantly higher in the control group (12.2%), while the lowest was observed in the pre-eclampsia group (1.18%) and T1DM (not planned) (1.26%). The placental leptin expression within each DM group was increased among the patients with unplanned pregnancy and those who received insulin therapy. We observed the lowest Lep expression in the PE group (6.3%). High level of HIF-1α expression was detected in T1DM (not planned) (30.44%) and PE (29.64%) as compared to the control group (11.62%). In T2DM and GDM insulin groups, the HIF-1α expression was significantly higher as compared to diet groups.

CONCLUSION

The obtained data show that DM and pre-eclampsia are associated with changes in angiogenic and metabolic placental factor expressions. The degree of changes depends on preconception care and the control of glycemia level during pregnancy.

Early second trimester maternal serum markers in the prediction of gestational diabetes mellitus

AIMS/INTRODUCTION

To determine whether maternal serum markers in the early second trimester are useful for prediction of gestational diabetes mellitus (GDM).

MATERIALS AND METHODS

A total of 876 singleton pregnancies were recruited in the present study. Blood samples were collected during 16-20 gestational weeks. GDM women were diagnosed by an oral glucose tolerance test during 24-28 gestational weeks. A total of 56 women with GDM and 73 healthy pregnant women were selected. Maternal serum concentrations of placental protein 13 (PP13), pentraxin 3 (PTX3), soluble fms-like tyrosine kinase-1 (sFlt-1), myostatin and follistatin (FST) were detected at 16-20 weeks' gestation. All of these markers concentrations were expressed as multiples of the medians. The Mann-Whitney U-test was used for comparison of the multiples of the medians of different concentrations of these five serum markers between the GDM group and the control group. Receiver operating characteristic curve analysis was applied to assess the sensitivity and specificity of significant serum markers from a Mann-Whitney U-test comparison.

RESULTS

Compared with healthy pregnancies, the serum levels of PP13, PTX3, sFlt-1, myostatin and FST in the early second trimester were significantly increased in patients who had developed GDM late. In screening for GDM by PP13, PTX3, sFlt-1, myostatin and FST, the detection rates were 92.3, 94.9, 94.9, 92.5 and 92.3%, respectively at 80% specificity. PTX3 and sFlt-1 were the most sensitive markers.

CONCLUSIONS

Maternal serum markers including PP13, PTX3, sFlt-1, myostatin and FST increase in the early second trimester of women with GDM. These five markers, especially PTX3 and sFlt-1, could have the value of prediction for those patients who would develop GDM in the late second trimester.

Second-trimester maternal serum markers in the prediction of preeclampsia

AIM

To determine whether late second-trimester maternal serum biomarkers are useful for the prediction of preeclampsia during the third trimester, a case-control study including 33 preeclamptic and 71 healthy pregnancies was conducted. Maternal serum concentrations of placental protein 13 (PP13), pregnancy-associated plasma protein (PAPP-A), pentraxin3 (PTX3), soluble FMS-like tyrosine kinase-1 (sFlt-1), myostatin and follistatin-like-3 (FSLT-3) were measured at 24-28 weeks' gestation. All the concentrations of these markers were compared between the preeclamptic and control groups. Receiver operating characteristic (ROC) curve analysis was applied to assess sensitivity and specificity of serum markers with significant difference.

RESULTS

The levels of PP13 and sFlt-1 were significantly increased and FSLT3 was significantly decreased in patients with preeclampsia. However, the concentration of PAPPA, PTX3 and myostatin did not differ significantly. In screening for preeclampsia during the third trimester by PP13, sFlt-1 and FSLT3, the detection rate was 61.3%, 48.1% and 39.1%, respectively, at 80% specificity, and the detection rate increased to 69.8% by combination of these three markers.

CONCLUSION

Maternal serum levels of PP13, sFlt-1 and FSLT3 play an important role in predicting late-onset preeclampsia, and the combination of these three markers significantly increases the detection rate for prediction.

The prediction of late-onset preeclampsia: Results from a longitudinal proteomics study

BACKGROUND

Late-onset preeclampsia is the most prevalent phenotype of this syndrome; nevertheless, only a few biomarkers for its early diagnosis have been reported. We sought to correct this deficiency using a high through-put proteomic platform.

METHODS

A case-control longitudinal study was conducted, including 90 patients with normal pregnancies and 76 patients with late-onset preeclampsia (diagnosed at ≥34 weeks of gestation). Maternal plasma samples were collected throughout gestation (normal pregnancy: 2-6 samples per patient, median of 2; late-onset preeclampsia: 2-6, median of 5). The abundance of 1,125 proteins was measured using an aptamers-based proteomics technique. Protein abundance in normal pregnancies was modeled using linear mixed-effects models to estimate mean abundance as a function of gestational age. Data was then expressed as multiples of-the-mean (MoM) values in normal pregnancies. Multi-marker prediction models were built using data from one of five gestational age intervals (8-16, 16.1-22, 22.1-28, 28.1-32, 32.1-36 weeks of gestation). The predictive performance of the best combination of proteins was compared to placental growth factor (PIGF) using bootstrap.

RESULTS

1) At 8-16 weeks of gestation, the best prediction model included only one protein, matrix metalloproteinase 7 (MMP-7), that had a sensitivity of 69% at a false positive rate (FPR) of 20% (AUC = 0.76); 2) at 16.1-22 weeks of gestation, MMP-7 was the single best predictor of late-onset preeclampsia with a sensitivity of 70% at a FPR of 20% (AUC = 0.82); 3) after 22 weeks of gestation, PlGF was the best predictor of late-onset preeclampsia, identifying 1/3 to 1/2 of the patients destined to develop this syndrome (FPR = 20%); 4) 36 proteins were associated with late-onset preeclampsia in at least one interval of gestation (after adjustment for covariates); 5) several biological processes, such as positive regulation of vascular endothelial growth factor receptor signaling pathway, were perturbed; and 6) from 22.1 weeks of gestation onward, the set of proteins most predictive of severe preeclampsia was different from the set most predictive of the mild form of this syndrome.

CONCLUSIONS

Elevated MMP-7 early in gestation (8-22 weeks) and low PlGF later in gestation (after 22 weeks) are the strongest predictors for the subsequent development of late-onset preeclampsia, suggesting that the optimal identification of patients at risk may involve a two-step diagnostic process.

Metabolic abnormalities and obesity's impact on the risk for developing preeclampsia

Preeclampsia (PE), a hypertensive disorder of pregnancy, is increasing as a major contributor to perinatal and long-term morbidity of mother and offspring. PE is thought to originate from ischemic insults in the placenta driving the release of prohypertensive anti-angiogenic [soluble fms-like tyrosine kinase-1 (sFlt-1)] and proinflammatory [tumor necrosis factor-α (TNF-α)] factors into the maternal circulation. Whereas the increased incidence of PE is hypothesized to be largely due to the obesity pandemic, the mechanisms whereby obesity increases this risk are unknown. The maternal endothelium is targeted by placental and adipose tissue-derived factors like sFlt-1 and TNF-α that promote hypertension during pregnancy, resulting in vascular dysfunction and hypertension. Interestingly, not all obese pregnant women develop PE. Data suggest that obese pregnant women with the greatest metabolic abnormalities have the highest incidence of PE. Identifying obesity-related mechanisms driving hypertension in some obese pregnant women and pathways that protect normotensive obese pregnant women, may uncover novel protocols to treat PE. Metabolic abnormalities, such as increased circulating leptin, glucose, insulin, and lipids, are likely to increase the risk for PE in obese women. It is not only important to understand whether each of these metabolic factors contribute to the increased risk for PE in obesity, but also their cumulative effects. This is particularly relevant to obese pregnant women with gestational diabetes mellitus (GDM) where all of these factors are increased and the risk for PE is highest. It is speculated that these factors potentiate the anti-angiogenic and proinflammatory mechanisms of placental ischemia-induced vascular dysfunction thereby contributing to the increasing incidence of PE.

Pre-eclampsia part 1: current understanding of its pathophysiology

Pre-eclampsia is characterized by new-onset hypertension and proteinuria at ≥20 weeks of gestation. In the absence of proteinuria, hypertension together with evidence of systemic disease (such as thrombocytopenia or elevated levels of liver transaminases) is required for diagnosis. This multisystemic disorder targets several organs, including the kidneys, liver and brain, and is a leading cause of maternal and perinatal morbidity and mortality. Glomeruloendotheliosis is considered to be a characteristic lesion of pre-eclampsia, but can also occur in healthy pregnant women. The placenta has an essential role in development of this disorder. Pathogenetic mechanisms implicated in pre-eclampsia include defective deep placentation, oxidative and endoplasmic reticulum stress, autoantibodies to type-1 angiotensin II receptor, platelet and thrombin activation, intravascular inflammation, endothelial dysfunction and the presence of an antiangiogenic state, among which an imbalance of angiogenesis has emerged as one of the most important factors. However, this imbalance is not specific to pre-eclampsia, as it also occurs in intrauterine growth restriction, fetal death, spontaneous preterm labour and maternal floor infarction (massive perivillous fibrin deposition). The severity and timing of the angiogenic imbalance, together with maternal susceptibility, might determine the clinical presentation of pre-eclampsia. This Review discusses the diagnosis, classification, clinical manifestations and putative pathogenetic mechanisms of pre-eclampsia.

The role of angiogenic and antiangiogenic factors in the second trimester in the prediction of preeclampsia in pregnant women with type 1 diabetes

OBJECTIVE

To assess the association between circulating angiogenic and antiangiogenic factors in the second trimester and risk of preeclampsia in women with type 1 diabetes.

RESEARCH DESIGN AND METHODS

Maternal plasma concentrations of placental growth factor (PlGF), soluble fms-like tyrosine kinase 1 (sFlt-1), and soluble endoglin (sEng) were available at 26 weeks of gestation in 540 women with type 1 diabetes enrolled in the Diabetes and Preeclampsia Intervention Trial.

RESULTS

Preeclampsia developed in 17% of pregnancies (n = 94). At 26 weeks of gestation, women in whom preeclampsia developed later had significantly lower PlGF (median [interquartile range]: 231 pg/mL [120-423] vs. 365 pg/mL [237-582]; P < 0.001), higher sFlt-1 (1,522 pg/mL [1,108-3,393] vs. 1,193 pg/mL [844-1,630] P < 0.001), and higher sEng (6.2 ng/mL [4.9-7.9] vs. 5.1 ng/mL[(4.3-6.2]; P < 0.001) compared with women who did not have preeclampsia. In addition, the ratio of PlGF to sEng was significantly lower (40 [17-71] vs. 71 [44-114]; P < 0.001) and the ratio of sFlt-1 to PlGF was significantly higher (6.3 [3.4-15.7] vs. 3.1 [1.8-5.8]; P < 0.001) in women who later developed preeclampsia. The addition of the ratio of PlGF to sEng or the ratio of sFlt-1 to PlGF to a logistic model containing established risk factors (area under the curve [AUC], 0.813) significantly improved the predictive value (AUC, 0.850 and 0.846, respectively; P < 0.01) and significantly improved reclassification according to the integrated discrimination improvement index (IDI) (IDI scores 0.086 and 0.065, respectively; P < 0.001).

CONCLUSIONS

These data suggest that angiogenic and antiangiogenic factors measured during the second trimester are predictive of preeclampsia in women with type 1 diabetes. The addition of the ratio of PlGF to sEng or the ratio of sFlt-1 to PlGF to established clinical risk factors significantly improves the prediction of preeclampsia in women with type 1 diabetes.

Diabetes and the kidney in pregnancy

The prevalence of diabetes in pregnant women is increasing, with 4% of deliveries in the United States occurring in women with pregestational or gestational diabetes. The proteinuria of late pregnancy is exaggerated in women with diabetes. However, diabetic women with preserved renal function before pregnancy appear to have little risk of deterioration of kidney function during pregnancy. Women with impaired renal function before pregnancy may be at risk for permanent decline of renal function during pregnancy, although it is unclear whether this represents the effect of pregnancy or the natural history of their diabetic renal disease. Preeclampsia, which is more common in women with diabetes, may be difficult to diagnose in this group of women. From the currently available literature, there appears to be no negative effect of pregnancy on the long-term progression of diabetic renal disease if renal function is normal and marked proteinuria is absent, but in light of recent findings in which preeclampsia appears to be associated with an increased risk of end-stage renal disease, large cohort studies will be necessary before this question can be definitively answered.

Insulin resistance: the possible link between gestational diabetes mellitus and hypertensive disorders of pregnancy

Gestational hypertension, preeclampsia, and diabetes are all associated with increased risks of poor maternal and perinatal outcomes. Pregnant women with gestational diabetes have been shown in population studies to have increased risk of pregnancy-associated hypertension compared with nondiabetic women. Moreover, pregnant patients with hypertension are at increased risk for developing gestational diabetes mellitus. It has been hypothesized that this association could be due, at least in part, to insulin resistance. Although insulin resistance is a physiologic phenomenon in normal pregnancy, in predisposed individuals this could lead to hyperinsulinemia with the development of gestational hypertension, gestational diabetes mellitus, or both.

Plasma sFlt-1-to-PlGF ratio is correlated with inflammatory but not with oxidative stress in Chinese preeclamptic women

PURPOSE

Considerable interest has been focused on angiogenic factors and angiogenic imbalance in the field of pre-eclampsia (PE), owing to its gaining role in the development of PE. This study was addressed to investigate the associations of sFlt-1-to-PlGF plasma ratios with oxidative stress assessed by the level of 8-isoprostane, and inflammation measured by the level of high-sensitive C-reactive protein (hs-CRP), and adipocytokines.

METHODS

A total of 83 patients with PE including 47 mild PE (MPE) and 36 severe PE (SPE) and 50 age-matched normotensive subjects in the third trimester of pregnancy were examined. Measurements included body mass index (BMI), systolic and diastolic blood pressure (BP) levels, plasma concentrations of hs-CRP, 8-isoprostane, adiponectin, and leptin.

RESULTS

Subjects with PE had higher levels of sFlt-1/PlGF (P < 0.01), hs-CRP (P < 0.01), 8-isoprostane and leptin (both P < 0.01) and lower adiponectin (P < 0.01) than did normotensive control subjects. Significant positive correlations were found between plasma sFlt-1/PlGF and hs-CRP (r = 0.437, P < 0.01) or leptin (r = 0.656, P < 0.01). A weak inverse correlation emerged between sFlt-1/PlGF and adiponectin (r = -0.306, P < 0.01). When a multiple regression analysis was performed, with sFlt-1/PlGF as a dependent variable and all the other parameters as independent variables, sFlt-1/PlGF maintain a significant relationship with leptin (beta = 0.219, P < 0.05) and with hs-CRP (beta = 0.295, P < 0.01) as well as with systolic BP(beta = 0.446, P < 0.05).

CONCLUSIONS

In Chinese preeclamptic women, plasma sFlt-1-to-PlGF ratio is correlated with inflammatory and adipocytokines but not with oxidative stress.