Low placental angiotensin-converting enzyme expression is related to fetal small for gestational age but not to metabolic control in type 1 diabetic pregnancies

The maternal renin-angiotensin system is involved in blood pressure control and plays a crucial role in fetoplacental nutrition. Pre-gestational type 1 diabetes (PGDM) leads to serious pregnancy complications. We thus performed a longitudinal study to analyse the association of maternal angiotensin-converting enzyme (ACE) serum levels and placental mRNA expression with fetal newborns gestational weight in type 1 diabetes mellitus (T1DM) women. We recruited 65 singleton pregnant women with T1DM. Placental mRNA ACE gene expression was examined using quantitative real-time PCR. Serum ACE levels were measured in the first, second and third trimesters of pregnancy by ELISA commercial kits. Placental expression of ACE mRNA was significantly lower in small for gestational age (SGA) than appropriate for gestational age (AGA) and large for gestational age (LGA) mothers (0.55±0.06 vs 0.78±0.06 and 0.85±0.07 respectively, p=0.003). In the SGA group, the mRNA expression of ACE positively correlated with maternal body mass index (BMI) in the third trimester (r=0.49; p=0.04). In all study groups maternal ACE level was significantly higher in the third trimester (mean 139.91±SD 69.64) compared to the first and second trimesters of pregnancy (13.57±4.32 and 15.69±15.92 respectively). Our data suggest that lower placental ACE gene mRNA expression may have a vital role in the etiology of SGA babies.

Low placental visfatin expression is related to impaired glycaemic control and fetal macrosmia in pregnancies complicated by type 1 diabetes

Type 1 diabetes mellitus (T1DM) is still related to altered fetal growth and severe maternal complications. We studied the possible role of placental visfatin/nicotinamide phosphoribosyltransferase (NAMPT) in fetal development in T1DM pregnancies, the possible role of placental visfatin in fetal macrosomia. Sixty five pregnant women with T1DM and singleton pregnancy were qualified into the study. Placental visfatin expression was by analysed by RT-PCR. We demonstrated the lowest expression of placental visfatin in women who delivered neonates with birth weight NBW > 4000 g (0.76 ± 0.05, P < 0.055). The highest placental visfatin/nicotinamide phosphoribosyltransferase (NAMPT) expression was found in the women who delivered small for gestational age (SGA) and large for gestational age (LGA) newborns (1.09 ± 0.95 vs. 0.87 ± 0.67, P < 0.05, respectively). There was also significant negative correlation between placental visfatin (NAMPT) expression and metabolic status in the 3^rd trimester of pregnancy in T1DM LGA group, defined as long-term glycaemic control (3^rd trimester HbA1C) - Pearson rank R - 08667654, P < 0.034. We conclude that the low placental visfatin (NAMPT) expression and poor metabolic control in the 3^rd trimester of pregnancy may have a role in stimulating fetal overgrowth in T1DM pregnancy.

Concentrations of endothelial nitric oxide synthase, angiotensin-converting enzyme, vascular endothelial growth factor and placental growth factor in maternal blood and maternal metabolic status in pregnancy complicated by hypertensive disorders

Hypertensive disorders of pregnancy (HDPs) are associated with altered maternal metabolism, impaired perinatal outcome and increased risk for remote maternal complications. The aim of our study was to analyse associations between circulating levels of angiogenic factors and markers of oxidative stress and metabolic status in women with HDP. Forty-six women in singleton pregnancies complicated by HDP and 30 healthy controls were enrolled in a prospective observational study. Serum concentrations of endothelial nitric oxide synthase (eNOS), angiotensin-converting enzyme, vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) were measured in the third trimester and correlated with maternal anthropometrics and metabolic status. We found significantly lower eNOS levels in patients with severe hypertension vs controls, a strong association between eNOS and PlGF in the study group, a significant association between maternal prepregnancy body mass index (BMI) and VEGF levels and an inverse correlation between VEGF and PlGF. Maternal prepregnancy BMI was the only independent predictor for VEGF concentrations. We noted reduced levels of PlGF and eNOS and increased VEGF levels in women with severe hypertension/preeclampsia. First, different forms of HDP are associated with different alteration patterns in concentrations of angiogenic factors and markers of oxidative stress. Second, maternal prepregnancy BMI, but not body weight, is a significant predictor for VEGF levels in late pregnancy.

Placental vascular endothelial growth factor expression in pregnancies complicated by type 1 diabetes

Type 1 diabetes mellitus (T1DM) is still associated with increased risk of severe maternal and foetal complications but their pathomechanism remains unclear.

OBJECTIVES

we investigated the possible role of placental vascular endothelial growth factor (VEGF) and VEGF single nucleotide polymorphisms (SNP) in foetal development in T1DM pregnancies. Sixty seven pregnant women with T1DM and singleton pregnancy were enrolled into the study. Results demonstrated higher expression of placental VEGF in women who delivered neonates with birth weight (NBW)>4000g. No such correlation was found in the overall T1DM group and in women who delivered appropriate for gestational age (AGA) and small for gestational age (SGA) newborns. We also demonstrated a significant correlation between 3(rd) trimester mean blood glucose, HbA1C and placental VEGF. No such correlation was found for the 1(st) and 2(nd) trimesters. Top placental VEGF expression and placental mass were found in women who delivered large for gestational age (LGA) newborns. We also found a statistically significant difference in homozygous and heterozygous frequency variants of VEGF SNPs in study groups. We conclude that the increased placental VEGF together with impaired metabolic control may have a role in stimulating foetal overgrowth in T1DM pregnancy.

Placental leptin and its receptor genes expression in pregnancies complicated by type 1 diabetes

Type 1 diabetes mellitus (T1DM) is still associated with increased risk for severe maternal and fetal complications but their pathomechanism remains unclear. We investigated into possible role of placental leptin (LEP) and its receptor gene (LEPR) in T1DM pregnancies. Fourty nine pregnant women with T1DM and singleton pregnancy were enrolled into the study. Control group consisted of 15 healthy pregnant women in uncomplicated, singleton gestation. We observed higher expression of LEP and LEPR in T1DM placentas in comparison to healthy subjects. We also noticed greater expression of LEP and LEPR in T1DM pregnancies with large for gestational age (LGA) and appropriate for gestational age (AGA) fetuses in comparison to small for gestational age (SGA) diabetic fetuses and controls. We found a significant positive correlation between placental LEP and LEPR expression and neonatal birthweight in overweight T1DM subjects. No such a correlation was found in T1DM subjects with normal weight and controls. We conclude that increased placental LEP and LEPR expression may have a role in stimulating fetal overgrowth in T1DM pregnancy.

Metabolic syndrome in type 1 diabetes mellitus. Does it have any impact on the course of pregnancy?

To determine whether the symptoms of metabolic syndrome (MS), if accompanied by oxidative stress (OS), in type 1 diabetes mellitus (DM) patients could affect the course of pregnancy and the perinatal outcome. Oxidized low density lipoproteins (ox-LDL) and total lipid peroxides (TLP) were studied in 98 pregnant women with type 1 DM in the I(st) and III(rd) trimesters. 24% of the participants met the criteria of MS. Vascular complications were significantly more frequent in the MS-group (41.9% vs. 17.4% in the non-MS group, p<0.05). No differences in the markers of OS between the MS and the non-MS groups were noted in either the I(st) or the III(rd) trimester. A significant gestational rise in Per-Ox was found in both groups. Chronic hypertension was associated with significant differences in ox-LDL levels in both the I(st) and III(rd) trimester. No differences in perinatal outcome, as measured by abnormal birth weight or poor neonatal status (Apgar score<6, umbilical venous and/or arterial pH<7.20), were found.

CONCLUSIONS

1) MS in type 1 DM is associated with some changes in markers of oxidative stress, but it poses no additional risk to the course of pregnancy and perinatal outcome in properly controlled and treated pregnant women with type 1 DM. 2) Maternal hypertension is the only component of MS in diabetic pregnancy that is associated with significant changes in markers of oxidative stress. 3) MS is significantly more frequent in diabetic pregnant women with co-existing vascular complications and obesity.

Leptin gene, leptin gene polymorphisms and body weight in pregnant women with diabetes mellitus type I

There have been several genetic causes of obesity discussed by past authors, among others leptin, that have provided information regarding signaling pathways in energy expenditure in humans. Genetic variants of the leptin gene and its receptor may influence body weight.

AIM

To investigate the role of the leptin gene's polymorphism promotion region (2548 G/A) and the leptin gene receptor polymorphism (668 A/G) and its associations with body weight in pregnant women with type 1 diabetes (PGDM-1).

METHODS

78 PGDM-1 were qualified to the study group (SG) which was divided into normal and over-weight individuals according to BMI criteria. The control group (CG) consisted of first trimester healthy pregnant women with normal body weight. Genetic variants of the leptin gene and its receptor were analyzed using PCR-RFLP assays. Within the SG, the following metabolic parameters were estimated: MBG, HbA1C, insulin dose, LDL, HDL, T-CHOL, creatinine, creatinine clearance and blood pressure.

RESULTS

There was a trend found among the majority of homozygous A and G variants in LEP -2548 G/A and LEPR 668 A/G in over-weight and obese individuals in comparison to normal-weight subjects (CG). There were no specific differences found in selected first trimester metabolic parameters in relation to patients' genotypes.