Functional polymorphisms of NOS3 and GUCY1A3 affect both nitric oxide formation and association with hypertensive disorders of pregnancy

Impaired nitric oxide (NO) formation may be associated with endothelial dysfunction and increased cardiovascular disease risk in preeclampsia (PE). Functional single-nucleotide polymorphisms (SNPs) of nitric oxide synthase 3 (NOS3) (rs3918226) and guanylate cyclase 1, soluble, alpha 3 (GUCY1A3) (rs7692387) increase susceptibility to the adverse consequences due to inadequate generation of NO by the endothelium. However, no previous study has examined whether these SNPs affect NO formation in healthy pregnancy and in gestational hypertension (GH) and PE. Here, we compared the alleles and genotypes of NOS3 (rs3918226) and GUCY1A3 (rs7692387) SNPs in normotensive pregnant women (NP, n = 153), in GH (n = 96) and PE (n = 163), and examined whether these SNPs affect plasma nitrite concentrations (a marker of NO formation) in these groups. We further examined whether the interaction among SNP genotypes is associated with GH and PE. Genotypes were determined using TaqMan allele discrimination assays, and plasma nitrite concentrations were determined by an ozone-based chemiluminescence assay. Multifactor dimensionality reduction was used to examine the interactions among SNP genotypes. Regarding NOS3 rs3918226, the CT genotype (p = 0.046) and T allele (p = 0.020) were more frequent in NP than in GH, and GH patients carrying the CT+TT genotypes showed lower nitrite concentrations than NP carrying the CT+TT genotypes (p < 0.05). Regarding GUCY1A3 rs7692387, the GA genotype (p = 0.013) and A allele (p = 0.016) were more frequent in PE than in NP, and NP women carrying the GG genotype showed higher nitrite concentrations than GH or PE patients carrying the GG genotype (p < 0.05). However, we found no significant interactions among genotypes for these functional SNPs to be associated with GH or PE. Our novel findings suggest that NOS3 rs3918226 and GUCY1A3 rs7692387 may affect NO formation and association with hypertensive disorders of pregnancy.

Plasma eNOS Concentration in Healthy Pregnancy and in Hypertensive Disorders of Pregnancy: Evidence of Reduced Concentrations in Pre-Eclampsia from Two Independent Studies

Hypertensive disorders of pregnancy (HDP), comprising gestational hypertension (GH) and pre-eclampsia (PE), are leading causes of maternal and perinatal morbidity and mortality. Both GH and PE are characterized by new-onset hypertension, but PE additionally includes proteinuria and/or end-organ damage. Impaired nitric oxide (NO) bioavailability may lead to endothelial dysfunction in GH and PE, and the primary source of vascular NO is endothelial NO synthase (eNOS). However, no previous study has investigated plasma eNOS concentrations in patients with GH and PE. In this study, we compared plasma eNOS concentrations in healthy pregnancies and HDP in two independent cohorts. The primary study included 417 subjects, with 43 non-pregnant (NP) and 156 healthy pregnant (HP) women and 122 patients with GH and 96 with PE. The replication study included 85 pregnant women (41 healthy and 44 pre-eclamptic). Plasma concentrations of eNOS were measured using a commercial ELISA kit provided by R&D Systems, and plasma nitrite concentrations were assessed using two ozone-based chemiluminescence assays. Correlations between plasma eNOS concentrations and plasma nitrite concentrations, as well as clinical and biochemical parameters, were evaluated by either Spearman's or Pearson's tests. In the primary study, NP women and HDP had significantly lower plasma eNOS concentrations compared to HP; concentrations were even lower in PE compared to GH. Plasma eNOS concentrations were reduced but not significant in early-onset PE, PE with severe features, preterm birth, and intrauterine growth restriction. No correlation was observed between plasma eNOS and nitrite levels. In HDP, there was a significant positive correlation between levels of eNOS and hemoglobin (r = 0.1496, p = 0.0336) as well as newborn weight (r = 0.1487, p = 0.0316). Conversely, a negative correlation between eNOS levels and proteinuria was observed (r = -0.2167, p = 0.0179). The replication study confirmed significantly reduced plasma concentrations of eNOS in PE compared to HP. Our findings provide evidence of reduced plasma eNOS concentrations in HDP; they were particularly lower in PE compared to GH and HP in two independent studies.

Longitudinal Study of Plasma Visfatin/Nicotinamide Phosphoribosyltransferase (NAMPT) Levels in Healthy Pregnant Women

Visfatin/nicotinamide phosphorybosil transferase (NAMPT) is a novel adipocytokine with potential roles in the pathophysiology of metabolic disorders, including gestational disorders. However, there is no clear interpretation regarding the circulating visfatin levels in a healthy pregnancy. Therefore, we conducted the first longitudinal study of plasma visfatin levels that followed up healthy pregnant women until the third trimester, including the postpartum period (PPP). The study recruited healthy women with singleton pregnancy who were not using any drug (including tobacco and alcohol). We have excluded pregnant women who did not attend all scheduled exams and developed gestational diabetes or hypertension, obesity, preeclampsia, or any infections during pregnancy. Nine women were considered eligible and examined during all three trimesters of pregnancy and between 8 and 12 weeks postpartum (PPP). Visfatin/NAMPT concentrations were measured in EDTA-plasma by ELISA. The mean age of pregnant women included was 22±5 years (54% primiparous), and the mean of gestational age at delivery was 40±1.2 weeks. Mean systolic and diastolic blood pressures were 90 and 70 mmHg, respectively. Mean values (± standard error mean) of visfatin concentrations (μg/L) during trimesters were 11.38±1.45 (first, 11-14 weeks), 9.18±1.82 (second, 20-24 weeks), 18.67±2.65 (third, 34-36 weeks), and 10.12±1.49 in the PPP. The value of the third trimester was significantly higher than the second trimester, and significantly reduced in the PPP (p<0.05, ANOVA with Bonferroni's multiple comparison tests). Visfatin/NAMPT levels are significantly lower in the PPP, suggesting that factors stimulating its production would be limited to pregnancy, thereby contributing to its potential application as a biomarker in pregnancy complications.

Cytokine quantification and association with cervical length in a prospective cohort of pregnant women

BACKGROUND

Preterm birth is a leading cause of infant morbidity and mortality; its multifactorial causes are an obstacle to understanding etiology and pathogenesis. The importance of cytokines and inflammation in its etiology and association with the short cervix is nowadays well-proven. To date, there are no reliable biological or biochemical markers to predict preterm birth; even though the length of the cervix has high specificity, its sensitivity with the cervix below 2.5 cm is low.

OBJECTIVE

We study the association of plasma cytokine levels and cervical length in search of predictors of preterm birth.

STUDY DESIGN

We evaluated a total of 1400 pregnant women carrying a single fetus between 20 and 25 weeks of gestation, and 1370 of them after childbirth in a nested case-control study of a prenatal cohort. Eligible pregnant women were interviewed and submitted to obstetric morphological and transvaginal ultrasound with cervical length measurement, gynecological examination, and blood collection. Preterm birth occurred in 133 women, 129 included in the study, and a control group randomly selected at a 2:1 ratio. A total of 41 cytokines with a higher probability of being associated with preterm birth or being of significance during labor were determined.

RESULTS

Cytokine and cervical length analysis by multivariate analysis of the conditional interference tree revealed that growth-related oncogene values of less than 2293 pg/mL were significantly associated with a cervical length of less than 2.5 cm.

CONCLUSIONS

As well as a cervical length shorter than 2.5 cm, growth-related oncogene levels of less than 2293 pg/ml may be associated with an increased risk of PB. Analysis based on the association of biomarkers and of the interaction between cytokines is a promising pathway in search of a predictor of preterm birth.

Circulating levels of tissue inhibitor of metalloproteinase 3, a protein with inhibitory effects on angiogenesis, are increased in pre-eclampsia

OBJECTIVE

To assess and compare circulating tissue inhibitor of metalloproteinase 3 (TIMP-3) concentrations between women with pre-eclampsia and healthy pregnant women. We also aimed to determine the relationships between circulating TIMP-3 and matrix metalloproteinase 2 (MMP-2), MMP-9, TIMP-1, and TIMP-2 concentrations in pre-eclampsia.

METHODS

A primary case-control study included patients with pre-eclampsia (n = 219) and gestational hypertension (n = 118), healthy pregnant women (n = 214), and non-pregnant women (n = 66), and a replication case-control study included patients with pre-eclampsia (n = 177) and healthy pregnant women (n = 124), all from southeastern Brazil. Plasma TIMP-3, MMP-2, MMP-9, TIMP-1, and TIMP-2 concentrations were assessed using commercially available enzyme-linked immunosorbent assay kits, and the relationships between them were analyzed using Spearman's correlation.

RESULTS

In our primary study, patients with pre-eclampsia and gestational hypertension exhibited increased TIMP-3 concentrations compared with healthy pregnant women (both P < 0.0001) and non-pregnant women (both P < 0.001). These findings were confirmed in the replication study, showing elevated TIMP-3 concentrations in women with pre-eclampsia versus healthy pregnant women (P < 0.001). We found no difference in TIMP-3 concentrations between early-onset and late-onset pre-eclampsia. Moreover, TIMP-3 concentrations were significantly correlated with plasma concentrations of TIMP-1 (r = 0.2333; P = 0.0086) and MMP-2 (r = 0.2159; P = 0.0156) in pre-eclampsia.

CONCLUSIONS

Circulating TIMP-3 concentration is increased in women with pre-eclampsia compared with healthy pregnant women, and it is positively correlated with plasma MMP-2 and TIMP-1 concentrations in pre-eclampsia.

ARG2 single-nucleotide polymorphism rs3742879 affects plasma arginase 2 levels, nitric oxide formation and antihypertensive therapy response in preeclampsia

Aim: This work examined whether ARG1 (rs2781659, rs2781667, rs2246012 and rs17599586) and ARG2 (rs3742879 and rs10483801) single-nucleotide polymorphisms (SNPs) are associated with antihypertensive therapy responsiveness in preeclampsia (PE) and their effects on arginase isoforms and nitrite concentrations in responsive and nonresponsive patients. Methods: SNP genotypes were determined by TaqMan assays. Plasma arginase levels were measured by ELISA and nitrite concentrations were measured using an ozone-based chemiluminescence assay. Results: The G allele for ARG2 rs3742879 (A>G) was less frequent in nonresponsive compared with responsive patients (15.5% vs 24.7%) and the G carriers of the nonresponsive subgroup had lower arginase 2 (9.2 ± 7.5 ng/ml vs 19.1 ± 17.3 ng/ml) and higher nitrite concentrations (110.2 ± 52.8 nM vs 78.5 ± 37.9 nM) than carriers of the AA genotype (all p < 0.05). Conclusion: ARG2 SNP rs3742879 is associated with diminished arginase 2 levels and increased nitric oxide formation in nonresponsive PE patients.

Circulating MicroRNAs in the Second Trimester From Pregnant Women Who Subsequently Developed Preeclampsia: Potential Candidates as Predictive Biomarkers and Pathway Analysis for Target Genes of miR-204-5p

MicroRNAs (miRNAs) play an important role in the pathophysiology of preeclampsia (PE). However, the expression of circulating miRNAs was not analyzed in the second trimester of pregnancy, a period of major relevance to identify predictive biomarkers for PE. Therefore, we examined the expression profiles of 84 circulating miRNAs using a PCR array in plasma collected between 20 and 25 weeks of gestation from pregnant women, who subsequently developed PE and those who remained healthy during pregnancy, randomly selected from a prospective cohort. Overall, 23 miRNAs had a fold change > 2.0 and were considered to be upregulated in plasma from pregnant women who subsequently developed PE, even before the onset of clinical symptoms of PE. However, only miR-204-5p was statistically significant (P = 0.0082). Experimentally validated interactions for the target genes of miR-204-5p extracted from miRTarBase were used in the gene set functional enrichment analysis to identify Reactome pathways. The network connecting the 37 target genes for miR-204-5p revealed pathways of known pathophysiological relevance during the early development of PE and included key genes related to PE, such as BDNF, MMP-9, MALAT1, TGFBR2, and SIRT1. We further depicted downstream targets of SIRT1 that are related to the vascular endothelial function or implicated in the pathophysiology of PE, namely, FOXO1, NFκB, HIF-1α, NOS3, and PPAR-γ. Our novel findings provide for circulating miRNAs upregulated in the second trimester on plasma from pregnant women who subsequently developed PE that is potentially related to the early development of PE, which may guide further studies focused on the validation of potential predictive biomarkers in PE.

Genital mycoplasma infection and spontaneous preterm birth outcome: a prospective cohort study

OBJECTIVE

To assess the risk of spontaneous preterm birth (sPTB) associated with genital mycoplasma infection in asymptomatic women.

DESIGN

Prospective cohort.

SETTING

Public and private health services in Ribeirão Preto, SP, Brazil.

POPULATION

A cohort of 1349 asymptomatic women with a singleton pregnancy at 20-25 weeks of gestation.

METHODS

Participants completed a sociodemographic and clinical history questionnaire during the prenatal visit and provided cervicovaginal samples for the evaluation of Mycoplasma hominis (Mh), Ureaplasma spp. and bacterial vaginosis (BV). For gestational outcome, information about the delivery was assessed and sPTB was defined as a birth that occurred before 37 weeks of gestation. The association between variables and the risk of sPTB was evaluated using logistic regression analysis to estimate the odds ratios (ORs).

MAIN OUTCOME MEASURES

Genital mycoplasma infection and prematurity.

RESULTS

The prevalence of sPTB and genital mycoplasma was 6.8 and 18%, respectively. The infection was not a risk factor for sPTB (aOR 0.66, 95% CI 0.32-1.35), even when Mh and Ureaplasma spp. were found together (P = 0.83). Pregnant women with genital mycoplasma infections had greater BV (P < 0.0001), but this vaginal microbiota condition was not associated with sPTB (P = 0.35). Regarding the risk factors associated with sPTB, a previous history of sPTB (aOR 12.06, 95% CI 6.21-23.43) and a cervical length of ≤2.5 cm (aOR 3.97, 95% CI 1.67-9.47) were significant.

CONCLUSIONS

Genital mycoplasma infection was not a risk factor for sPTB, even in the presence of other abnormal vaginal microbiota.

TWEETABLE ABSTRACT

Genital mycoplasma infection was not a risk for sPTB, even when associated with bacterial vaginosis (BV).

NAMPT single-nucleotide polymorphism rs1319501 and visfatin/NAMPT affect nitric oxide formation, sFlt-1 and antihypertensive therapy response in preeclampsia

Aim: We examined the relationships between visfatin/NAMPT and nitrite concentrations (a marker of nitric oxide [NO] formation) or sFlt-1 levels in 205 patients with preeclampsia (PE) responsive or nonresponsive to antihypertensive therapy, and whether NAMPT SNPs rs1319501 and rs3801266 affect nitrite concentrations in PE and 206 healthy pregnant women. Patients & methods: Circulating visfatin/NAMPT and sFlt-1 levels were measured by ELISA, and nitrite concentrations by using an ozone-based chemiluminescence assay. Results: In nonresponsive PE patients, visfatin/NAMPT levels were inversely related to nitrite concentrations and positively related to sFlt-1 levels. NAMPT SNP rs1319501 affected nitrite concentrations in nonresponsive PE patients and was tightly linked with NAMPT functional SNPs in Europeans. Conclusion: NAMPT SNP rs1319501 and visfatin/NAMPT affect NO formation, sFlt-1 levels and antihypertensive therapy response in PE.

Effects of arginase genetic polymorphisms on nitric oxide formation in healthy pregnancy and in preeclampsia

BACKGROUND AND AIMS

Preeclampsia is associated with reduced nitric oxide (NO) bioavailability. Arginase is related to NO synthesis, but relatively unexplored in preeclampsia. However, no previous study has examined whether variations in ARG1 and ARG2 genes affect NO bioavailability and the risk of preeclampsia. Here, we compared the alleles and genotypes of single nucleotide polymorphisms (SNPs) in ARG1 (rs2781659; rs2781667; rs2246012; rs17599586) and ARG2 (rs3742879; rs10483801) in healthy pregnant women and preeclampsia, and examined whether these SNPs affect plasma nitrite concentrations (a marker of NO formation) in these groups.

METHODS

Genotypes for the ARG1 and ARG2 SNPs were determined by Taqman probe and plasma nitrite by an ozone-based chemiluminescence assay.

RESULTS

Regarding ARG1 SNPs, the GG genotype and G allele frequencies for rs2781659, and the C allele frequencies for rs2246012 were higher in preeclampsia compared to healthy pregnant women. Moreover, the GG genotype for rs2781659 and the TT genotype for rs2781667 were associated with higher plasma nitrite in healthy pregnant. We found no association of ARG2 polymorphisms with preeclampsia or nitrite levels in the study groups.

CONCLUSIONS

Our results suggest that SNPs of ARG1 increase the risk of preeclampsia and modulate plasma nitrite levels in healthy pregnant women.

Circulating Total Cell-Free DNA Levels Are Increased in Hypertensive Disorders of Pregnancy and Associated with Prohypertensive Factors and Adverse Clinical Outcomes

Previous studies have described increased circulating cell-free DNA (cfDNA) in hypertensive disorders of pregnancy (HDP). Here, we aimed first to confirm this information using a simple, but sensible fluorescent assay, and second to investigate whether total cfDNA is associated with circulating factors known to be linked to the pathophysiology of HDP as well as with poor maternal-fetal outcomes. We studied 98 women with healthy pregnancies (HP), 88 with gestational hypertension (GH), and 91 with preeclampsia (PE). Total DNA was extracted from plasma using the QIAamp DNA blood mini kit and quantified using Quant-iT™ PicoGreen® dsDNA fluorescent detection kit. We found higher total cfDNA levels in GH and PE (197.0 and 174.2 ng/mL, respectively) than in HP (140.5 ng/mL; both p < 0.0001). Interestingly, total cfDNA levels were elevated in both male and female-bearing pregnancies diagnosed with either HDP, and in more severe versus less severe HDP cases, as classified according to responsiveness to antihypertensive therapy. In addition, total cfDNA was independently associated with HDP, and a cutoff concentration of 160 ng/mL provided appropriate sensitivity and specificity values for diagnosing GH and PE compared to HP (70-85%, both p < 0.0001). Moreover, high total cfDNA was associated with adverse clinical outcomes (high blood pressure, low platelet count, preterm delivery, fetal growth restriction) and high prohypertensive factors (sFLT-1, sEndoglin, MMP-2). These findings represent a step towards to the establishment of cfDNA as a diagnostic tool and the need to understand its role in HDP.

Association of genitourinary infections and cervical length with preterm childbirth

A prospective cohort study was conducted on a convenience sample of 1370 pregnant women with a gestational age of 20 to 25 weeks in the city of Ribeirão Preto. Data on obstetrical history, maternal age, parity, smoking habit, and a history of preterm delivery was collected with the application of a sociodemographic questionnaire. Cervical length was determined by endovaginal ultrasound, and urine and vaginal content samples were obtained to determine urinary tract infection (UTI) and bacterial vaginosis (BV), respectively. The aim of this study was to verify the association of cervical length and genitourinary infections with preterm birth (PTB). Ultrasound showed no association of UTI or BV with short cervical length. PTB rate was 9.63%. Among the women with PTB, 15 showed UTI (RR: 1.55, 95%CI: 0.93–2.58), 19 had BV (RR: 1.22, 95%CI: 0.77–1.94), and one had both UTI and BV (RR: 0.85, 95%CI: 0.13–5.62). Nineteen (14.4%) PTB occurred in women with a cervical length ≤2.5 cm (RR: 2.89, 95%CI: 1.89–4.43). Among the 75 patients with PTB stratified as spontaneous, 10 showed UTI (RR: 2.02, 95%CI: 1.05–3.86) and 14 had a diagnosis of BV (RR: 1.72, 95%CI: 0.97–3.04). A short cervical length between 20 and 25 weeks of pregnancy was associated with PTB, whereas UTI and BV determined at this age were not associated with short cervical length or with PTB, although UTI, even if asymptomatic, was related to spontaneous PTB.

Is birth weight associated with pregestational maternal BMI? BRISA Cohort, Ribeirão Preto, Brazil

Given the increase of women with excess weight or obesity and its possible effects on birth weight, the present study aimed to investigate the association between pregestational maternal body mass index (BMI) and birth weight in a birth cohort from Ribeirão Preto, SP, Brazil. This was a prospective study conducted on 1362 mother-child pairs involving singleton births. The women were evaluated using standardized questionnaires during the second trimester of pregnancy and at the time of childbirth. Information about the newborns was obtained from their medical records. The dependent variable was birth weight, categorized as low, adequate, or high. The independent variable was pregestational maternal BMI, categorized as malnutrition, adequate weight, overweight, and obesity. A multinomial regression model was used to estimate the crude and adjusted relative risk (RR) of low and high birth weight. A high frequency of pregestational excess weight (39.6%) was detected and found to be independently associated with high birth weight (RR=2.13, 95%CI: 1.19-3.80 for overweight and RR=3.34, 95%CI: 1.80-6.19 for obese pregnant women). There was no association between pregestational malnutrition and low birth weight (RR=1.70; 95%CI: 0.81-3.55). The present data showed a high rate of women with excess pregestational weight, supporting the hypothesis that pregestational BMI may contribute to high birth weight babies and indicating the need for actions aiming to prevent excessive weight in women at reproductive age.

Uterine vascular resistance and other maternal factors associated with the risk of developing hypertension during pregnancy

Gestational hypertension and pre-eclampsia are important causes of perinatal morbidity. The objective of the present study was to determine the increase in relative risk for developing hypertensive disorders of pregnancy based on the evaluation of pregnant women between 20 and 25 weeks of gestation, and to correlate the findings at this period with the outcome of pregnancy. We conducted a prospective cohort study, with a convenience sample of 1417 patients evaluated at this gestational age, of which 1306 were contacted at childbirth. We detected an increased relative risk of 2.69 (95%CI: 1.86 to 3.89) associated with pulsatility index of the uterine arteries, a 2.8 increase (95%CI: 1.58 to 5.03) in relative risk attributed to maternal age above 35 years, a 1.68 increase (95%CI: 1.17 to 2.40) attributed to parity greater than or equal to 3, and a 5.35 increase (95%CI: 4.18 to 6.85) attributed to chronic hypertension and obesity, with a progressive increase in relative risk according to the degree of overweight, i.e., grades 1, 2, 3, and morbid obesity (2.58, 3.06, 5.84, and 7.28, respectively).

Can increased resistance to uterine artery flow be a risk factor for adverse neurodevelopmental outcomes in childhood? A prospective cohort study

A prospective cohort study was conducted to determine whether an increased uterine artery pulsatility index (UtA-PI) in the second trimester of pregnancy is a risk factor for neurodevelopmental outcomes in children 2-3 years of age. A group of pregnant women with a UtA-PI below the 90th percentile (P90) and a second group with a UtA-PI ≥ P90 in the second trimester were included in this study. The children of these women were evaluated during their second or third year of life using the Bayley III Screening Test. A total of 858 pregnancies with UtA-PI < P90 and 96 pregnancies with UtA-PI ≥ 90 were studied. The differences between the groups related to UtA-PI ≥ 90 were detected in relation to the variables of the Caucasian ethnicity, hypertension, newborn weight and stay in the intensive care unit after birth. However, adjusted neurodevelopmental outcomes did not differ between the groups: OR 0.53 (95% CI 0.27-1.04%). This study failed to demonstrate that the UtA-PI is a risk factor for adverse neurodevelopment in children.Impact statementWhat is already known on this subject? Early interventions in children at high risk for neurodevelopmental deficiency have proved to be beneficial. The complications associated with gestation and delivery negatively influence neurodevelopment. Several studies have shown that some adverse pregnancy outcomes such as preeclampsia, foetal growth restriction and foetal death can be predicted by increased resistance to flow in the uterine artery in the second trimester. However, there are no studies evaluating the association of the uterine artery with neurodevelopmental results.What do the results of this study add? This study concludes that neurodevelopment is influenced by multiple environmental and intrinsic factors and cannot be predicted by only one variable, such as the uterine artery blood flow. The brain has repair mechanisms to attenuate insults that occur during gestation and delivery.What are the implications of these findings for clinical practice and/or further research? This study was unable to demonstrate that blood flow in the uterine artery is a risk factor for neurodevelopment. Different, larger studies should be conducted by combining other factors with the uterine artery in an algorithm to allow the early identification of children at risk for neurodevelopmental impairment.

Prevalence and Risk Factors for Microcephaly at Birth in Brazil in 2010

OBJECTIVES

To estimate the baseline prevalence and risk factors for microcephaly at birth before the Zika virus epidemic in 2 Brazilian cities.

METHODS

We used population-based data from the Brazilian Ribeirão Preto (RP) and São Luís (SL) birth cohort studies of 2010 that included hospital deliveries by resident mothers. The final sample was 7376 live births in RP and 4220 in SL. Gestational age was based on the date of the mother's last normal menstrual period or obstetric ultrasonography, if available. Microcephaly at birth was classified according to the criteria of the International Fetal and Newborn Growth Consortium for the 21st Century and the Brazilian Ministry of Health. Risk factors for microcephaly, proportionate and disproportionate microcephaly, and severe microcephaly were estimated in a hierarchized logistic regression model.

RESULTS

According to the International Fetal and Newborn Growth Consortium for the 21st Century definition, the prevalence of microcephaly (>2 SDs below the mean for gestational age and sex) was higher in SL (3.5%) than in RP (2.5%). The prevalence of severe microcephaly (>3 SDs below the mean) was higher in SL (0.7%) than in RP (0.5%). Low maternal schooling, living in consensual union or without a companion, maternal smoking during pregnancy, primiparity, vaginal delivery, and intrauterine growth restriction were consistently associated with microcephaly. The number of cases of microcephaly is grossly underestimated, with an underreporting rate of ∼90%.

CONCLUSIONS

The prevalence of severe microcephaly was much higher than expected in both cities. Our findings suggest that microcephaly was endemic in both municipalities before the circulation of the Zika virus.

Higher levels of circulating TIMP-4 in preeclampsia is strongly associated with clinical parameters and microRNA

BACKGROUND

Preeclampsia results in maternal and fetal complications and some studies have reported the role of MMPs and TIMPs in its pathophysiology. Therefore, the aim of this study was to compare plasma TIMP-4 levels in preeclampsia and healthy pregnant; and to correlate these levels with clinical parameters and expression of Let7a-5p (3´UTR post-transcriptionally regulation) Methods: TIMP-4 was measured by ELISA and miR-Let7a-5p expression by qPCR.

RESULTS

Elevated plasma TIMP-4 levels in preeclampsia compared to healthy pregnant was found 1450 ± 411 vs. 775 ± 210 pg/mL, respectively (p < 0.0001); these levels are correlated positively with serum liver enzymes (ALT, r = 0.84, p = 0.004; and AST, r = 0.51, p = 0.02); and negatively with newborn weight (r = -0.45, p = 0.04) in preeclampsia. Regarding Let7a-5p a negative but not significant correlation was found (r = -0.39, p = 0.06, including both healthy and preeclampsia).

CONCLUSIONS

Preeclampsia present elevated levels of circulating TIMP-4 compared to healthy pregnant and these levels are correlated with clinical parameters of disease.

Glutamatergic and neural dysfunction in postpartum depression using magnetic resonance spectroscopy

Although postpartum depression (PPD) is a prevalent subtype of major depressive disorder, neuroimaging studies on PPD are rare, particularly those identifying neurochemical abnormalities obtained by proton magnetic resonance spectroscopy (¹H-MRS). The dorsolateral prefrontal (DLPF) and the anterior cingulate gyrus (ACG) are part of the neural pathways involved in executive functions and emotional processing, and both structures have been implicated in the neurobiology of depressive disorders. This study aimed to evaluate brain metabolites abnormalities in women with PPD compared with healthy postpartum (HP) women. Thirty-six PPD (34 without antidepressants) and 25 HP women underwent a ¹H-MRS acquired on a 3-T MRI system, with the volume of interest positioned in ACG and DLPF. An ANCOVA was conducted with age, postpartum time, and contraceptive type as covariates. PPD group presented significantly lower Glutamate+Glutamine (Glx, -0.95mM) and N-acetylaspartate+N-acetylaspartylglutamate (NAA, -0.60mM) values in DLPF. There were no significant differences between groups in ACG, but we found a significant increase of Glutamate (Glu, 2.18mM) and Glx (1.84mM) in participants using progestogen-only contraceptives. These findings suggest glutamatergic dysfunction and neuronal damage in the DLPF of PPD patients, similarly to other subtypes of depressive disorders. Progestogens seem to interfere in the neurochemistry of ACG.

Pharmacogenetics in the treatment of pre-eclampsia: current findings, challenges and perspectives

Pre-eclampsia (PE) is defined as pregnancy-induced hypertension and proteinuria, and is a major cause of maternal and perinatal morbidity and mortality. A large subgroup of pregnant women with PE is nonresponsive to antihypertensive drugs, including methyldopa, nifedipine and hydralazine. Pharmacogenomics may help to guide the individualized therapy for this nonresponsive subgroup. However, just a few pharmacogenetic studies examined the effects of genetic polymorphisms on response to antihypertensive drugs in PE, and the criteria of responsiveness used to define responsive or nonresponsive subgroups to antihypertensive therapy should be replicated by others. We review these gene–drugs interactions, novel approaches to pharmacogenomics research and potential novel drugs for PE therapy. Finally, we discuss the challenges and perspectives of pharmacogenetics in the treatment of PE.

Induced Human Decidual NK-Like Cells Improve Utero-Placental Perfusion in Mice

Decidual NK (dNK) cells, a distinct type of NK cell, are thought to regulate uterine spiral artery remodeling, a process that allows for increased blood delivery to the fetal-placental unit. Impairment of uterine spiral artery remodeling is associated with decreased placental perfusion, increased uterine artery resistance, and obstetric complications such as preeclampsia and intrauterine growth restriction. Ex vivo manipulation of human peripheral blood NK (pNK) cells by a combination of hypoxia, TGFß-1 and 5-aza-2'-deoxycytidine yields cells with phenotypic and in vitro functional similarities to dNK cells, called idNK cells. Here, gene expression profiling shows that CD56Bright idNK cells derived ex vivo from human pNK cells, and to a lesser extent CD56Dim idNK cells, are enriched in the gene expression signature that distinguishes dNK cells from pNK cells. When injected into immunocompromised pregnant mice with elevated uterine artery resistance, idNK cells homed to the uterus and reduced the uterine artery resistance index, suggesting improved placental perfusion.

Antihypertensive therapy in pre-eclampsia: effects of plasma from nonresponsive patients on endothelial gene expression

Aim: Over 40% of patients with pre-eclampsia are nonresponsive to antihypertensive therapy, but the underlying mechanisms are unknown. We examined the effects of plasma from nonresponsive and responsive patients on endothelial gene expression. Patients & methods: PCR array was performed in human umbilical vein endothelial cells (HUVEC) incubated with plasma from nonresponsive (n = 4) and responsive (n = 4) patients. Gene networks and interactions with antihypertensive drugs used in pre-eclampsia were identified by Ingenuity Pathway Analysis. Results: Nifedipine and hydralazine act by upregulate or downregulate genes found to be downregulated or upregulated in HUVEC incubated with plasma from nonresponsive patients. Conclusion: Our novel findings suggest that plasma from nonresponsive and responsive patients evoke different responses in HUVEC, and might advance the pharmacogenomics research in pre-eclampsia.

Plasma from pre-eclamptic patients induces the expression of the anti-angiogenic miR-195-5p in endothelial cells

We examined the effect of plasma incubation from preeclampsia pregnant on the antiangiogenic miR-195-5p expression. Higher miR-195-5p expression was found in cultures incubated with preeclampsia plasma compared to those incubated with healthy pregnant plasma. Next, as VEGF is a target of miR-195-5p we have quantified its expression by real-time qPCR and ELISA. We found reduced VEGF levels in culture incubated with preeclampsia plasma. Therefore, we have concluded that the higher expression of miR-195-5p in endothelial cell cultures incubated with preeclampsia plasma may contribute to decreased expression of VEGFA (gene and protein) and increased antiangiogenic status in preeclampsia. Therefore, this miR may be an important target in preeclampsia.

Role of adiponectin on antioxidant profile: evaluation during healthy and hypertensive disorders of pregnancy

The study of adipokines and oxidative stress has aided in understanding pre-eclampsia physiopathology. Therefore, our group aimed to evaluate the correlation between the adipokines (adiponectin and leptin) and the oxidative stress marker malondialdehyde-thiobarbituric acid reactive substances (MDA-TBARS) and antioxidant activity of plasma [ferric reducing ability of plasma (FRAP)] in healthy pregnant women and patients with gestational hypertension and pre-eclampsia. We found a significant negative correlation between MDA-TBARS and adiponectin (r = -0.40, p = 0.0042), suggesting a relationship between antioxidant levels and this adipokine in healthy pregnancies which is altered in patients with gestational hypertension or pre-eclampsia.

Circulating microRNA expression profiles in pre-eclampsia: evidence of increased miR-885-5p levels

OBJECTIVE

To validate and to compare the circulating microRNA (miR) expression profiles between pre-eclampsia and healthy pregnant women, to perform correlation analysis of the differently expressed miRs with clinical and biochemical parameters, and to verify the extracellular localisation of miRs in apoptotic bodies, microvesicles, and exosomes.

DESIGN

A case-control study with a replication study.

SETTING

Pregnant women attending maternity hospitals in Southeastern Brazil.

POPULATION

Two obstetric white populations: a case-control study (19 pre-eclampsia and 14 healthy pregnant) and a replication study (eight pre-eclampsia and eight healthy pregnant).

METHODS

PCR-array with 84 different miRs was performed in plasma from five pre-eclampsia and four healthy pregnant women. In the case-control study, differently expressed miRs were validated using quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), and correlated with clinical and biochemical parameters. The plasma was then fractioned to study the extracellular localisation of miRs.

MAIN OUTCOME MEASURES

Gene expression profiles of miRs.

RESULTS

From PCR-array, three miRs (miR-376c-3p, miR-19a-3p, and miR-19b-3p) were found to be down-regulated and the miR-885-5p was found to be up-regulated in pre-eclampsia compared with healthy pregnant women. In the validation step, miR-885-5p was the only significantly different miR (fold-change = 5.0, P < 0.05), which was confirmed in the replication study (fold-change = 4.5, P < 0.05). Moreover, miR-885-5p was significantly correlated with the hepatic enzyme aspartate transaminase (r = 0.66; P = 0.0034) and it was mostly associated with the exosomes (32-fold higher than apoptotic bodies).

CONCLUSIONS

miR-885-5p is increased in plasma from pre-eclampsia compared with healthy pregnant women, and it is released into circulation mainly inside exosomes. TWEETABLE ABSTRACT: miR-885-5p is increased in pre-eclampsia and is released into circulation mainly inside exosomes.

Correlations between circulating levels of adipokines and anti-angiogenic factors in women with BMI <30 and a late-onset preeclampsia

Preeclampsia (PE) is a pregnancy-specific disease, directly related to high rates of maternal-fetal morbidity and mortality worldwide. Upregulation of anti-angiogenic factors (soluble fms-like tyrosine kinase-1; sFLT-1 and soluble endoglin; sENG) have been suggested to trigger the maternal endothelial dysfunction observed in PE. Studies focusing on the role of adiponectin and leptin, in normal pregnancy as well as in complicated pregnancies, have revelated interesting findings due to the vascular actions of such adipokines. The aims of this study were to compare plasma concentrations of the adiponectin, leptin, sENG and sFLT-1 in preeclamptic (PE, n = 27) and healthy pregnant (HP, n = 36) and to evaluate possible correlations among these adipokines and anti-angiogenic factors. There were significant increases in all biomarkers in PE compared to HP (all p < 0.05). In PE group, there were positive strong correlations among adiponectin and leptin with sFLT-1 (r = 0.85 and r = 0.47, respectively) and sEng (r = 0.74 and r = 0.56, respectively). Moreover, we observed significantly correlation among body mass index (BMI) with adiponectin (r = -0.40) and with leptin (r = 0.51) in HP, but not in PE. Moreover, while a negative correlation between sFLT-1 and BMI (r = -0.60) was found in PE, no correlation was observed regarding sEng and BMI. In summary, our findings suggest the existence of a compensatory mechanism that occurs in an attempt to correct this angiogenic imbalance in order to restore the fetal development.

Positive correlations between circulating adiponectin and MMP2 in preeclampsia pregnant

OBJECTIVE

The aims of the present study were to compare plasma concentrations of the adiponectin, leptin, metalloproteinases (MMP9 and MMP2) and its tissue inhibitors (TIMP1 and TIMP2) in preeclamptic (PE) and healthy pregnant (HP) groups and correlate them.

METHODS

A total of 105 pregnant women with pre-pregnancy body mass index (BMI) values ⩽ 30 kg/m(2) were enrolled for this study (59 PE and 46 HP). Biomarkers were measured using ELISAs.

RESULTS

Adiponectin (32%), leptin (45%), MMP2 (20%), TIMP1 (31%) and TIMP2 (23%) levels were higher in PE compared to HP (all P < 0.05). In addition there were positive correlations between adiponectin and MMP2 (r = 0.33; P = 0.03) and adiponectin and TIMP2 (r = 0.33; P = 0.03) in PE group, but not in HP.

CONCLUSION

Our findings show that adiponectin, leptin, MMP2, TIMP1 and TIMP2 levels are increased in PE and adiponectin may contribute to higher levels of MMP2 and TIMP2 in this disease.

Correlations among antiangiogenic factors and trace elements in hypertensive disorders of pregnancy

Although a number of studies have measured circulating levels of some trace elements in preeclampsia (PE) and compared to healthy pregnant (HP), there is no consensus yet about the deficiency of some metals and development of hypertensive disorders in pregnancy. The aim of this study was to compare plasmatic levels of Zn, Mn, Co, Cu, Se and Sr among non-pregnant (NP), healthy pregnant (HP), gestational hypertensive (GH) and preeclamptic (PE) women and to correlate these levels with plasma soluble endoglin (sENG) and soluble fms-like tyrosine kinase-1 (sFLT-1), two important antiangiogenic proteins related to PE. A total of 184 women were enrolled in this study (NP=35, GH=51, PE=37 and HP=61). Trace element analyses were carried out with an inductively coupled plasma mass spectrometer (ICPMS). sENG and sFLT-1 plasma concentrations were measured by commercial ELISA kits. The most interesting result is that Sr is higher in PE (63%, P<0.001) compared to HP and their levels are positively correlated with sENG in all three groups of pregnant women. Moreover, we found a negative correlation between Zn and sENG in HP (r=-0.43, P=0.003). Regarding other elements, we found similar levels among pregnant groups. In conclusion, this study showed that Sr may has a role in physiopathology of PE.

Antihypertensive therapy in preeclampsia is not modulated by VEGF polymorphisms

INTRODUCTION

Vascular endothelial growth factor (VEGF) is relevant for healthy pregnancy, and abnormalities in VEGF functions have been associated with hypertensive disorders of pregnancy. Our group recently demonstrated that VEGF genetic polymorphisms affect the susceptibility to preeclampsia (PE).

OBJECTIVE

Therefore, in this study our aim is to examine whether VEGF polymorphisms affect the antihypertensive responses in women with PE.

METHODS

We studied 113 white PE women who were stratified according to blood pressure levels after antihypertensive treatment (46 responsive, R group and 67 non-responsive, NR group). We then compared the frequencies of two VEGF genetic polymorphisms (C-2578A and G-634C) between R and NR groups.

RESULTS

We found no significant differences in genotype or allele distributions between R and NR groups (P > 0.05). In addition, no difference was observed in overall distribution of haplotypes (P > 0.05).

CONCLUSION

Our data suggest that VEGF polymorphisms do not affect responsiveness to the antihypertensive therapy in PE.

Obesity and pregnancy: a transversal study from a low-risk maternity

BACKGROUND

Obesity is a public health problem and is increasing in all populations, including pregnant women. It influences maternal and neonatal outcomes; however, data are scarce in developing countries. We aimed to compare perinatal results between obese and non-obese pregnant women in a low-risk maternity.

METHODS

Transversal study of 1,779 40-week-pregnancies from 2005 to 2009 that completed a standard questionnaire with sociodemographic, obstetrical and neonatal variables and performed an ultrasound with amniotic fluid index (AFI) measurement and foetal vitality (FBP, non-stress test). They were analysed about their association with obesity on pregnancy.

RESULTS

When compared with non-obese women, the group of obese patients had higher systolic (118.1 vs 109.2 mmHg; p < 0.01) and diastolic (76.6 vs 70.4 mmHg; p < 0.01) pressure levels, AFI (12.52 vs. 9.61 cm; p = 0.02), presence of meconium on labour (20.52 vs. 14.67%; p = 0.02), birthweight (3602 vs. 3437 g; p < 0.01) and caesarean section (39.74 vs. 29.98%, p < 0.01).

CONCLUSIONS

Labour induction before 40 weeks in the antenatal period associated with foetal weight estimation should be considered as a recommendation for decreasing high percentages of caesarean delivery found in obese women.

Tissue inhibitor of matrix metalloproteinase-1 polymorphism, plasma TIMP-1 levels, and antihypertensive therapy responsiveness in hypertensive disorders of pregnancy

Tissue inhibitor of metalloproteinase (TIMP)-1 is a major endogenous inhibitor of matrix metalloproteinase (MMP)-9, which may affect the responsiveness to therapy in hypertensive disorders of pregnancy. We examined whether TIMP-1 polymorphism (g.-9830T>G, rs2070584) modifies plasma MMP-9 and TIMP-1 levels and the response to antihypertensive therapy in 596 pregnant: 206 patients with preeclampsia (PE), 183 patients with gestational hypertension (GH) and 207 healthy pregnant controls. We also studied the TIMP-3 polymorphism (g.-1296T>C, rs9619311). Plasma MMP-9 and TIMP-1 levels were measured by ELISA. GH patients with the GG genotype for the TIMP-1 polymorphism had lower MMP-9 levels and MMP-9/TIMP-1 ratios than those with the TT genotype. PE patients with the TG genotype had higher TIMP-1 levels. The G allele and the GG genotype were associated with PE and responsiveness to antihypertensive therapy in PE, but not in GH. Our results suggest that the TIMP-1 g.-9830T>G polymorphism not only promotes PE but also decreases the responses to antihypertensive therapy.

Maternal flow-mediated dilation and nitrite concentration during third trimester of pregnancy and postpartum period

OBJECTIVES

To compare maternal flow-mediated dilation (FMD) of the brachial artery and nitrite concentration between third trimester of pregnancy (3rdT) and postpartum (PP) period. Additionally, we will evaluate whether FMD correlates with nitrite concentration in both periods.

METHODS

Eligibility criteria was healthy women with singleton pregnancy, gestational age >28 weeks, nonsmokers, and no personal or family history of vascular disease. Each women was examined during 3rdT and between 8 and 12 weeks PP to evaluate FMD and nitrite concentration in whole blood. Women not examined in both periods were excluded. Values between both periods were compared using paired t tests. Correlation between FMD and nitrite was examined by Pearson correlation coefficient. Significance level set as p < 0.05.

RESULTS

We invited 42 pregnant women. Among them, 35 were eligible and 7 of them were excluded for not attending the PP evaluation resulting in 28 participants analyzed. We found no significant change in FMD (10.39 ± 5.57% vs. 8.42 ± 4.21%; p = 0.11; 3rdT vs. PP, respectively) and no significant change in nitrite concentration (257.41 ± 122.95 nmol/L vs. 237.16 ± 90.01 nmol/L; p = 0.28). Baseline brachial artery diameter had a significant reduction (3.11 ± 0.30 to 2.75 ± 0.34 mm; p < 0.01). No significant correlation between FMD and nitrite during 3rdT (r = -0.13; p = 0.50) or PP (r = 0.14; p = 0.48) was found.

CONCLUSIONS

We did not observe significant changes in both FMD and nitrite concentration between third trimester and the PP period. FMD did not correlate with nitrite in both periods. More studies are needed to confirm our findings.

Haptoglobin polymorphism affects nitric oxide bioavailability in preeclampsia

Studies showed elevated cell-free hemoglobin (Hb) in preeclampsia (PE), and Hb reacts with nitric oxide (NO), decreasing its bioavailability. Haptoglobin (Hp) is a polymorphic protein (Hp1-1, Hp2-1 and Hp2-2) that binds Hb to form a complex that is removed from circulation, thus preventing Hb-driven oxidative stress and NO scavenging. Hp protein products differ in biochemical and biophysical properties, which reflects on the Hb-Hp complex clearance rate. We hypothesized that Hp phenotypes modulate NO bioavailability by influencing NO consumption in PE. We studied 92 PE subjects and 105 normal pregnant women (NP). Hp genotypes were determined using real-time PCR. To assess NO bioavailability, we measured plasma nitrite using an ozone-based chemiluminescence assay. Plasma Hb and Hp were assessed with commercial immunoassays. A NO consumption assay was used to measure NO consumption. We found no differences in Hp genotype frequencies between PE and NP groups. Hp genotypes had no effects on plasma heme levels, NO consumption and plasma nitrite in NP. However, in PE, Hp2-1 and Hp2-2 were associated with higher plasma heme levels (48 and 55% higher, respectively; P<0.05), increased NO consumption (42 and 44% more, respectively; P<0.05) and lower plasma nitrite (39% less for Hp2-2; P<0.05) compared with Hp1-1. These findings indicate that although Hp genotype does not affect the risk of PE, Hp1-1 genotype may exert a protective role in PE by reducing NO scavenging, whereas Hp2-1 and Hp2-2 further may aggravate PE by reducing NO bioavailability.

eNOS tag SNP haplotypes in hypertensive disorders of pregnancy

Haplotypes formed by polymorphisms (T-786C, rs2070744; a variable number of tandem repeats in intron 4, and Glu298Asp, rs1799983) of the eNOS gene were associated previously with gestational hypertension (GH) and preeclampsia (PE). However, no study has explored the Tag SNPs rs743506 and rs7830 in these disorders. The aim of the current study was to compare the distribution of the genotypes and haplotypes formed by the five eNOS polymorphisms mentioned among healthy pregnant (HP, n=122), GH (n=138), and PE (n=157). The haplotype formed by "C b G G C" was more frequent in HP compared to GH and PE (p=0.0071), which is supported by previous findings that demonstrated the association of the combination "C b G" with a higher level of nitrite (NO marker). Our results suggest a protective effect of the haplotype "C b G G C" against the development of hypertensive disorders of pregnancy.

PP002. Study of polymorphisms of the adiponectin gene in women with gestational hypertension and preeclampsia

INTRODUCTION

Adiponectin is involved in energy homeostasis by regulating glucose and lipid metabolism. Additionally, it presents anti-inflammatory and anti-atherosclerotic functions. Polymorphisms in adiponectin gene (ADIPOQ) can modulate the concentrations of adiponectin. The influence of these polymorphisms on the development of gestational hypertension (GH) and preeclampsia (PE) is unknown.

OBJECTIVES

The aim of this work was to examine the influence of polymorphisms in the gene ADIPOQ on the development of gestational hypertension and preeclampsia.

METHODS

PATIENTS AND METHODS

We studied 401 pregnant women: 161 healthy pregnant (HP), 113 pregnant with gestational hypertension (GH) and 127 pregnant with preeclampsia (PE). Polymorphisms ADIPOQ -11391G>A (rs17300539), -11377C>G (rs266729), 45T>G (rs2241766) and 276G>T (rs1501299) were genotyped by allelic discrimination by PCR in real time. Haplotypes were inferred using the PHASE 2.1 program.

RESULTS

There were no statistically significant differences in allele and genotype frequencies of the polymorphisms studied. In the analysis of haplotypes, we observed small differences in haplotype frequencies between groups, however, none of these differences was statistically significant (P>0.05).

CONCLUSION

We found no association between the genotypic and allelic variants of the ADIPOQ gene polymorphisms with the development of gestational hypertension and preeclampsia.

Effects of matrix metalloproteinase (MMP)-2 polymorphisms on responsiveness to antihypertensive therapy of women with hypertensive disorders of pregnancy

Imbalanced matrix metalloproteinase (MMP) expression, including MMP-2, has been demonstrated in pre-eclampsia. However, little is known about the effect of polymorphisms in MMP-2 gene on hypertensive disorders of pregnancy. We examined whether two functional MMP-2 polymorphisms (g.-1306C>T and g.-735C>T) are associated with pre-eclampsia and/or gestational hypertension and whether these polymorphisms affect therapeutic responses in women with these conditions. We studied 216 healthy pregnant women (HP), 185 patients with gestational hypertension (GH) and 216 patients with pre-eclampsia (PE). They were stratified as responsive or non-responsive to antihypertensive therapy according to clinical and laboratorial parameters of therapeutic responsiveness. Genomic DNA was extracted from whole blood and genotypes for g-1306C>T and g.-735C>T polymorphisms were determined by real-time PCR using Taqman allele discrimination assays. Haplotype frequencies were inferred using the PHASE 2.1 program. The distributions of MMP-2 genotypes and haplotypes were similar in HP, GH and PE patients (p > 0.05). In addition, we found no significant differences in MMP-2 genotype or haplotype frequencies when GH or PE patients were classified as responsive or non-responsive to antihypertensive therapy (p > 0.05). Our results suggest that MMP-2 polymorphisms do not affect the susceptibility to hypertensive disorders of pregnancy. In parallel, MMP-2 polymorphisms apparently do not affect the responsiveness to antihypertensive therapy of women with these hypertensive disorders of pregnancy.

Association between matrix metalloproteinase (MMP)-2 polymorphisms and MMP-2 levels in hypertensive disorders of pregnancy

We examined whether two functional polymorphisms (g.-1306C>T and g.-735C>T) in matrix metalloproteinase (MMP)-2 gene are associated with preeclampsia (PE) or gestational hypertension (GH), and whether they modify MMP-2 or tissue inhibitor of metalloproteinase (TIMP)-2 plasma concentrations in these hypertensive disorders of pregnancy. We studied 130 healthy pregnant (HP), 130 pregnant with GH, and 133 pregnant with PE. Genomic DNA was extracted from whole blood and genotypes for g.-1306C>T and g.-735C>T polymorphisms were determined by Real Time-PCR, using Taqman allele discrimination assays. Haplotypes were inferred using the PHASE program. Plasma MMP-2 and TIMP-2 concentrations were measured by ELISA. The main findings were that pregnant with PE have higher plasma MMP-2 and TIMP-2 concentrations than HP (P<0.05), although the MMP-2/TIMP-2 ratios were similar (P>0.05). Moreover, pregnant with GH have elevated plasma MMP-2 levels and MMP-2/TIMP-2 ratios compared to HP (P<0.05). While MMP-2 genotypes and haplotypes are not linked with hypertensive disorders of pregnancy, MMP-2 genotypes and haplotypes are associated with significant alterations in plasma MMP-2 and TIMP-2 concentrations in preeclampsia (P<0.05). Our findings may help to understand the relevance of MMP-2 and its genetic polymorphisms to the pathophysiology of hypertensive disorders of pregnancy. It is possible that patients with PE and the MMP-2 haplotype combining the C and T alleles for the g.-1306C>T and g.-735C>T polymorphisms may benefit from the use of MMPs inhibitors such as doxycycline. However, this possibility remains to be determined.

Maternal iNOS genetic polymorphisms and hypertensive disorders of pregnancy

Increased expression and activity of inducible nitric oxide synthase (iNOS) may contribute to the pathogenesis of pre-eclampsia (PE) and gestational hypertension (GH). However, no previous study has examined whether genetic polymorphisms in the iNOS gene are associated with PE or GH. We examined whether two functional, clinically relevant iNOS genetic polymorphisms (the C(-1026)A polymorphism, rs2779249, in the promoter region, and the G2087A polymorphism, rs2297518, in exon 16) are associated with GH or with PE. We studied 565 pregnant women: 212 healthy pregnant (HP), 166 pregnant with GH and 187 pregnant with PE. Genotypes were determined by real-time PCR, using the Taqman allele discrimination assay. The PHASE 2.1 program was used to estimate haplotype distributions in the three study groups. We found no significant association between the C(-1026)A polymorphism and PE or GH (P>0.05). However, we found the GA genotype and the A allele for the G2087A polymorphism at higher frequency in PE, but not in GH, compared with HP (P<0.05). The haplotype analysis showed no significant intergroup differences (P>0.05). These findings suggest that iNOS genetic variants may affect the susceptibility to PE, but not to GH.

Alterations in cyclic GMP levels in preeclampsia may reflect increased B-type natriuretic peptide levels and not impaired nitric oxide activity

OBJECTIVES

We compared nitrite, B-type natriuretic peptide (BNP), and cGMP levels in preeclamptic with those found in healthy pregnant.

METHODS

We studied 21 healthy pregnant and 27 preeclamptic. Plasma cGMP and BNP levels were determined by ELISA. Nitrite levels were determined by chemiluminescence.

RESULTS

Higher cGMP and BNP, and lower nitrite levels were found in preeclamptic versus healthy pregnant.

CONCLUSIONS

Altered cGMP levels reflect increased BNP levels and not impaired nitric oxide activity in preeclampsia.

Changes in fetal and maternal Doppler parameters observed during acute severe hypertension treatment with hydralazine or labetalol: a randomized controlled trial

We evaluated 16 pregnant women with gestational age between 20 and 32 weeks in acute severe hypertension which were randomly allocated to receive either hydralazine or labetalol. Blood pressure and Doppler ultrasound parameters from maternal uterine and fetal middle cerebral and umbilical arteries were assessed during acute severe hypertension and after treatment. A significant reduction in systolic and diastolic blood pressure was observed in both groups. A significant change in Doppler parameters was observed only in pregnant women who received hydralazine: an increase in uterine arteries resistance index. We concluded that both drugs were highly effective in reducing blood pressure in these women. Despite the observed increase in resistance index of uterine arteries associated with hydralazine, the use of hydralazine and labetalol were not related to any significant changes in fetal Doppler, which is reassuring about the safety of these drugs when treating acute severe hypertension in pregnancy.

Increased circulating cell-free hemoglobin levels reduce nitric oxide bioavailability in preeclampsia

Contrasting with increased nitric oxide (NO) formation during healthy pregnancy, reduced NO bioavailability plays a role in preeclampsia. However, no study has examined whether increased NO consumption by enhanced circulating levels of cell-free hemoglobin plays a role in preeclampsia. We studied 82 pregnant women (38 healthy pregnant and 44 with preeclampsia). To assess NO bioavailability, we measured plasma and whole blood nitrite concentrations using an ozone-based chemiluminescence assay. Plasma ceruloplasmin concentrations and plasma NO consumption (pNOc) were assessed and plasma hemoglobin (pHb) concentrations were measured with a commercial immunoassay. We found lower whole blood and plasma nitrite concentrations in preeclamptic patients (-48 and -39%, respectively; both P<0.05) compared with healthy pregnant women. Plasma samples from preeclamptic women consumed 63% more NO (P=0.003) and had 53% higher pHb and 10% higher ceruloplasmin levels than those found in healthy pregnant women (P<0.01). We found significant positive correlations between pHb and pNOc (r=0.61; P<0.0001), negative correlations between pNOc and whole blood or plasma nitrite concentrations (P=0.02; r=-0.32 and P=0.01; r=-0.34, respectively), and negative correlations between pHb and whole blood or plasma nitrite concentrations (P=0.03; r=-0.36 and P=0.01; r=-0.38, respectively). These findings suggest that increased pHb levels lead to increased NO consumption and lower NO bioavailability in preeclamptic compared with healthy pregnant women.

Interethnic differences in ADMA concentrations and negative association with nitric oxide formation in preeclampsia

BACKGROUND

Recent studies have suggested that impaired nitric oxide (NO) formation in preeclampsia may result from increased concentrations of an endogenous NO synthase inhibitor, the asymmetric dimethylarginine (ADMA). However, no previous study has examined whether a negative association exists between ADMA and nitrite concentrations in preeclampsia. Moreover, no previous study has compared ADMA and nitrite levels in black and white preeclamptic pregnant women.

METHODS

We measured plasma nitrite concentrations using an ozone-based chemiluminescence assay, and plasma ADMA levels using enzyme immunoassays in 94 pregnant (47 healthy pregnant: 16 blacks and 31 whites; and 47 preeclamptic: 14 blacks and 33 whites).

RESULTS

We found higher ADMA (2.199 + or -0.016 micromol/l vs. 2.112 + or - 0.012 micromol/l; P<0.0001) and lower plasma nitrite levels (102 + or - 7.1 nmol/l vs. 214.8 + or - 26.1 nmol/l; P<0.0001) in preeclamptic compared with healthy pregnant women. Black pregnant had higher ADMA levels than white pregnant women (P<0.05), both in preeclamptic (2.239 + or - 0.020 micromol/l vs. 2.144 + or - 0.019 micromol/l) and in healthy pregnant (2.172 + or - 0.025 micromol/l vs. 2.077 + or - 0.018 micromol/l). Conversely, we found no significant effects of ethnicity on the plasma nitrite levels, both in healthy pregnant and in preeclamptic women (P>0.05). We found a significant negative correlation (P<0.05) between these markers (r=-0.28; P<0.05).

CONCLUSIONS

Our findings show higher ADMA and lower nitrite levels in preeclamptic compared with healthy pregnant, and the concentrations of these biomarkers are inversely associated. While ethnicity affected ADMA concentrations, no such effect was found with respect to nitrite levels. These results may have important implications for studies on NO biology and therapeutic approaches of preeclampsia.

Effects of eNOS polymorphisms on nitric oxide formation in healthy pregnancy and in pre-eclampsia

Pre-eclampsia (PE) is associated with decreased nitric oxide (NO) formation. However, no previous study has examined whether genetic variations in the endothelial NO synthase (eNOS) affect this alteration. We hypothesized that PE decreases NO formation depending on eNOS polymorphisms. We examined how three eNOS polymorphisms [T-786C, rs2070744; Glu298Asp, rs1799983; 27 bp variable number of tandem repeats (VNTR) in intron 4] affect plasma nitrite concentrations in 205 pregnant women [107 healthy pregnant (HP) and 98 PE]. Genotypes were determined and eNOS haplotypes were inferred using the PHASE 2.1 program. The plasma nitrite concentrations were determined using an ozone-based chemiluminescence assay. The Glu298Asp polymorphism had no effects on the plasma nitrite concentrations. Higher nitrite levels were found in HP women with the CC versus TT genotype for the T-786C polymorphism (277.9 +/- 19.5 versus 140.6 +/- 8.2 nM; P < 0.05). Lower nitrite levels were found in healthy women with the 4a4a versus 4b4b genotype for the VNTR polymorphism (95.1 +/- 3.3 versus 216.1 +/- 16.8 nM; P < 0.05). No effects of genotypes were found in PE women (all P > 0.05). The 'C Glu b' haplotype was more frequent in the HP group than in the PE group (20 versus 5; P = 0.0044). This haplotype was associated with higher nitrite concentrations than the other haplotypes in healthy pregnancies (P < 0.05). No differences in nitrite concentrations were found among PE women with different eNOS haplotypes (P > 0.05). These findings indicate that eNOS polymorphisms affect endogenous NO formation in normal pregnancy, but not in PE, and that the 'C Glu b' haplotype may protect against the development of PE by increasing endogenous NO formation.