Hypertension is the most common medical disorder in pregnancy, and a leading cause of maternal and neonatal morbidity and mortality. Vitamin D endocrine system has important influence on immune modulation and endothelial function, which play a role in preeclampsia (PE) and gestational hypertension (GH). Vitamin D receptor (VDR) is present in a large variety of cell types, including placental cells. We examined whether there is an association between VDR polymorphisms (FokI, ApaI and BsmI) with PE or with GH. Restriction fragment length polymorphism techniques were used to genotype 529 pregnant (154 with GH, 162 with PE, and 213 healthy pregnant-HP). VDR haplotype frequencies were inferred using the PHASE 2.1 program. We found similar genotype distributions for the three VDR polymorphisms in both PE and GH groups compared with the HP group (all P [ 0.05). In parallel with these findings, the VDR haplotype frequency distribution was similar in both PE and GH groups compared with the HP group (all P [ 0.05). Our results showing no significant association between VDR polymorphisms or haplotypes with PE or GH suggest that genetic variations in VDR do not predispose to hypertensive disorders of pregnancy.

Genetic factors influence whole blood lead (Pb-B) concentrations in lead exposed subjects. This study aimed at examining the combined effects (haplotype analysis) of three polymorphisms (BsmI, ApaI and FokI) in vitamin D receptor (VDR) gene on Pb-B and on the concentrations of lead in plasma (Pb-P), which is more relevant to lead toxicity, in 150 environmentally exposed subjects. Genotypes were determined by RFLP, and Pb-P and Pb-B were determined by inductively coupled plasma mass spectrometry and by graphite furnace atomic absorption spectrometry, respectively. Subjects with the bb (BsmI polymorphism) or ff (FokI polymorphism) genotypes have lower B-Pb than subjects in the other genotype groups. Subjects with the aa (ApaI polymorphism) or ff genotypes have lower P-Pb than subjects in the other genotype groups. Lower Pb-P, Pb-B, and %Pb-P/Pb-B levels were found in subjects with the haplotype combining the a, b, and f alleles for the ApaI, BsmI, and FokI polymorphisms, respectively, compared with the other haplotype groups, thus suggesting that VDR haplotypes modulate the circulating levels of lead in exposed subjects.

Foetal exposure to lead (Pb) during pregnancy is a major problem. However, no previous study has examined whether Pb concentrations in blood (Pb-B) and in serum (Pb-S) from pregnant women correlate with Pb-B and Pb-S in the foetuses. This hypothesis was tested in the present study. We measured Pb-B and Pb-S in 120 healthy pregnant women (more than 38 weeks of gestation) and their respective umbilical cord samples. The analyses were carried out with an inductively coupled plasma mass spectrometer. We found higher Pb-B levels in the women compared with their respective umbilical cord samples (1.736 € 0.090 lg ⁄ dL and 1.194 € 0.062 lg ⁄ dL, respectively; p < 0.05). In parallel, we found higher Pb-S levels in the women compared with their respective umbilical cord samples (0.042 € 0.003 lg ⁄ dL and 0.032 € 0.003 lg ⁄ dL, respectively; p < 0.05). However, similar %Pb-S ⁄ Pb-B ratios were found in the women compared with their respective umbilical cord samples (2.414 € 0.210% and 2.740 € 0.219%, respectively; p > 0.05). Interestingly, we found positive correlations between Pb-B in the umbilical cords and Pb-B in the respective pregnant women (rs = 0.5714; p < 0.0001), and between Pb-S in the umbilical cords and Pb-S in the respective pregnant women (rs = 0.3902; p < 0.0001) as well as between %Pb-B ⁄ Pb-S in the umbilical cords and %Pb-B ⁄ Pb-S in the respective pregnant women (rs = 0.3767; p < 0.0001). These results indicate that the assessment of Pb-B and Pb-S in pregnant women provides relevant indexes of foetal exposure to Pb. Moreover, the similar %Pb-S ⁄ Pb-B in pregnant women and in the umbilical cords shows that the foetuses are directly exposed to the rapidly exchangeable Pb fraction found in their mothers.Major concerns exist with regard to lead (Pb) exposure, which should not be found in the blood, especially during pregnancy. For example, lead exposure may affect and disrupt normal physiology as well as increase the oxidative stress [1]. The increased demands for calcium during pregnancy lead to increased bone turnover and increased circulating Pb levels [2,3]. Pb from the mother can easily cross the placenta [4] and expose the foetus to the harmful effects of Pb, thus affecting the embryonic development of multiple organ systems and causing retardation of cognitive development [5]. Indeed, recent results have indicated reduced intellectual development in children with a history of prenatal lead exposure [6].Because Pb accumulates in bone and has a half-life of years or decades, Pb transference to the foetus may take place even years after maternal exposure [3,7]. In order to study the impact of prenatal exposure to Pb, the concentrations of this metal are usually measured in maternal whole blood (Pb-B) [8][9][10]. Others have measured prenatal maternal bone Pb levels as an index of Pb burden [3,11]. However, it is not clear which is the best biomarker to assess lead exposure during pregnancy. It is possible that serum (Pb-S) or plasma (Pb-P) Pb concentrations may be better indexes of Pb exposur...

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