A longitudinal study of circulating angiogenic and antiangiogenic factors and AT1-AA levels in preeclampsia.

Our earlier studies of preeclampsia (PE) at delivery have demonstrated the alteration of one carbon cycle, reduced placental omega 3 fatty acids, altered circulating levels of angiogenic factors and differential placental gene-specific methylation patterns of angiogenic factors. This study was undertaken to examine changes in the levels of angiogenic factors and angiotensin II type 1 receptor autoantibodies (AT1-AAs) throughout gestation, from early pregnancy until delivery, in women with PE and to examine their association with cord angiogenic factors, blood pressure and infant weight. A total of 81 pregnant women (46 normotensive and 35 with PE) were followed at three different time points during pregnancy: 16-20 weeks (T1), 26-30 weeks (T2) and at the time of delivery (T3). The plasma levels of angiogenic factors and AT1-AAs were determined in the maternal and cord plasma by commercial enzyme-linked immunosorbent assay kits. Maternal plasma levels of vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) were lower (P<0.05 for both), whereas soluble fms-like tyrosine kinase-1 (sFlt-1; P<0.05) and the sFlt-1/PlGF ratio (P<0.01) were higher in early pregnancy in the PE group. Maternal plasma AT1-AA levels were higher (P<0.05) at T2 in women with PE. Cord plasma VEGF and soluble kinase insert domain receptor (sKDR) levels were lower (P<0.01 and P<0.05, respectively), whereas AT1-AA levels were higher (P<0.05) in the PE group. Maternal plasma VEGF levels in early pregnancy were positively associated with systolic blood pressure, whereas the sFlt-1/PlGF ratio at T2 was negatively associated with infant weight in the PE group. Low levels of proangiogenic factors (VEGF and PlGF) and high levels of AT1-AAs and antiangiogenic factors (sFlt-1 and sFlt-1/PlGF ratio) are present in the maternal circulation during early gestation in women with PE.

Maternal soluble fms-like tyrosine kinase-1, placental growth factor, plasminogen activator inhibitor-2, and folate concentrations and early fetal size: the Generation R study.

OBJECTIVE: Fetal growth is dependent on adequate development of the placenta. Impaired angiogenesis and vasculogenesis in early pregnancy compromises placental and embryonic development. The proteins soluble fms-like tyrosine kinase (sFlt)-1, placental growth factor (PlGF), and plasminogen activator inhibitor (PAI)-2, and the B vitamin folate are determinants of placental development. This study aims to identify associations between these maternal biomarkers and early fetal size. STUDY DESIGN: From a prospective birth cohort study in The Netherlands, 1491 pregnant women were selected for this study. At a mean gestational age (GA) of 12.4 weeks (SD 0.8) maternal venous blood samples were obtained to determine the concentrations of sFlt-1, PlGF, PAI-2, and folate. Early fetal size was assessed with measurement of the crown-to-rump length (CRL) at a mean of 12.4 weeks' GA (SD 0.8). Analyses were performed using multivariable linear regression analyses with the biomarkers (continuous, quintiles) as regressors and CRL as main outcome measure. RESULTS: Linear trend analysis showed positive associations between maternal sFlt-1 (P < .001), PlGF (P = .042), PAI-2 (P < .001), and folate (P = .039) and CRL. These associations were independent of GA, maternal age, height, body mass index, ethnicity, fetal sex, parity, educational level, smoking, and folic acid supplement use (folate not adjusted). CONCLUSION: sFlt-1, PlGF, PAI-2, and folate are positively associated with first-trimester fetal size.

Risks for preeclampsia and small for gestational age: predictive values of placental growth factor, soluble fms-like tyrosine kinase-1, and inhibin A in singleton and multiple-gestation pregnancies.

OBJECTIVE: To determine the accuracy of placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1), and inhibin A in singleton and multiple-gestation pregnancies for predicting preeclampsia (PE) and small for gestational age (SGA). STUDY DESIGN: A prospective cohort nested in a randomized controlled trial of antioxidant supplementation for the prevention of PE. Plasma biomarkers were evaluated at 12 to 18 (visit 1) and 24 to 26 (visit 2) weeks' gestation and expressed as adjusted multiples of the median. RESULTS: Multiple-gestation pregnancy (74/772) had a significant impact on all biomarkers' levels. PlGF was the best predictor of PE and SGA. At a 10% false-positive rate, PlGF at visit 1 had 21% sensitivity for predicting PE in singleton versus 60% in multiple-gestation pregnancies. PlGF at visit 1 had a 31% sensitivity in singleton and 27% in multiple-gestation pregnancies for SGA prediction. CONCLUSION: PlGF level was a good predictor of subsequent PE as early as 12 to 18 weeks in multiple-gestation pregnancies but was not clinically useful enough to be used as a single marker.

The effect of Kraussianone-2 (Kr2), a natural pyrano-isoflavone from Eriosema kraussianum, in an L-NAME- induced pre-eclamptic rat model.

This study aimed to investigate the effects of Kraussianone-2 (Kr2), a pyrano-isoflavone isolated from the roots of Eriosema kraussianum N. E. Br. (Fabaceae) on various fetal and physiological parameters in pregnant, L-NAME treated Sprague-Dawley rats. Twenty-four pregnant Sprague-Dawley dams were divided into three groups (n = 8), i.e. the control group (CON), the experimental control group (PRE), where the pre-eclampsia-like symptoms were induced using L-NAME, and the experimental group (EK2), where the pre-eclampsia-like symptoms were once again induced using L-NAME, however, these animals were treated with Kr2. On gestation day 20 the animals were sacrificed, at which time a laparotomy was performed and the number of live pups were counted and their corresponding birth and placental weights were recorded. Blood was also collected in heparin-coated tubes and the plasma samples were then analysed for specific variables using commercially available kits for rats. Kraussianone-2 administration decreased fetal mortality and demonstrated a trend toward increasing birth and placental weights in this model. Furthermore, Kr2 administration also reduced blood pressure amplification and decreased the plasma concentrations of two antiangiogenic factors, soluble fms-like tyrosine kinase1 (sFlt-1) and soluble endoglin (sEng). We speculate that Kr2, by improving uterine artery blood flow, results in improved fetal outcomes and decreased antiangiogenic factors in pregnant, L-NAME treated, Sprague-Dawley rats.

[Modern methods of early screening for preeclampsia and pregnancy-induced hypertension--a review]. / Wspólczesne metody wczesnej diagnostyki stanu przedrzucawkowego i nadcisnienia indukowanego ciaza.

Preeclampsia remains to be a serious perinatal complication and early screening for this disease to identify the high risk population before the first symptoms develop constitutes a considerable clinical challenge. Modern methods of screening for preeclampsia and pregnancy-induced hypertension include patients history biochemical serum markers and foetal DNA and RNA in maternal serum. They aid the process of developing an optimal protocol to initiate treatment in early pregnancy and to reduce the rate of complications. Our review presents an overview of the novel methods and techniques used for early screening for preeclampsia and pregnancy-induced hypertension. Most of the research focuses on 11-13 weeks of gestation due to the fact that the first prenatal examination is performed at that time. The most important information seems to be: weight, mass, mean blood pressure, history of pregnancy-induced hypertension or preeclampsia at previous pregnancies as well as the ethnic origin. During an ultrasound scan, pulsatility index of the uterine arteries is measured. Blood samples are obtained during the last part of the examination. At the moment only a few markers seem to be strong predictors of hypertensive disorders during pregnancy: pregnancy-associated plasma protein-A (PAPP-A), placental growth factor (PIGF) and soluble fms-like tyrosine kinase-1 (sFlt-1). Also, fetal DNA and RNA in maternal plasma are helpful in the prediction of preeclampsia as they are markers of the trophoblast apoptosis. Researchers aim at identifying the population at high risk of pregnancy-induced hypertension and preeclampsia in order to offer appropriate antenatal care to these women. At the moment many drugs and diet supplements are investigated to reduce the prevalence of hypertensive disorders in pregnancy. These medications are usually administrated in early gestation (up to 16 week of gestation) before the first clinical symptoms present. Low doses of aspirin were found to decrease the risk of preeclampsia in high-risk groups. Moreover, according to some recent research, also essential omega-3 fatty acids reduce the incidence of preeclampsia. None of the other investigated diet supplements or antioxidants were proven to successfully reduce incidents of hypertensive disorders. So far, there is available evidence on the lack of any effect for vitamines C, D or E. Further studies are necessary to define clinical useful markers of gestational hypertension.

Dietary treatments enriched in olive and safflower oils regulate seric and placental matrix metalloproteinases in maternal diabetes.

OBJECTIVES: Matrix metalloproteinases (MMPs) are proteolytic enzymes involved in placental development and function, although related to the pro-inflammatory environment when produced in excess. Previous studies have identified MMP-2 and MMP-9 overactivities in the placenta from diabetic rats. In this study, we aimed to determine whether diets supplemented with olive and safflower oil, enriched in natural PPAR ligands, are able to regulate MMP-2 and MMP-9 activities in the placenta and serum from diabetic rats. STUDY DESIGN: Diabetes was induced in rat neonates by streptozotocin administration (90mg/kg s.c.). Control and diabetic rats were fed with 6% olive oil- or 6% safflower oil-supplemented diets from days 0.5-13.5 of gestation. MAIN OUTCOME MEASURES: On day 13.5 of gestation, placentas and sera were isolated for further determination of matrix metalloproteinases (MMPs) 2 and 9 activities by zymography. Placental MMP-2 and MMP-9 protein concentration and immunolocalization were also determined. RESULTS: Sera from diabetic pregnant animals showed MMP-2 and MMP-9 overactivities when compared to controls. Serum MMP-9 activity was significantly decreased when the diabetic animals received the olive and safflower oil dietary treatments. Placentas from diabetic rats showed increased MMP-2 and MMP-9 activities and protein concentrations, and both were decreased when diabetic rats received the olive and safflower dietary treatments. CONCLUSIONS: This study demonstrates that both olive and safflower oil-supplemented diets were able to prevent MMPs overactivities in the placenta from diabetic rats, and that these beneficial effects are reflected in rat sera.

Iron in pregnancy: How do we secure an appropriate iron status in the mother and child?

Iron deficiency and iron deficiency anemia (IDA) during pregnancy are risk factors for preterm delivery, prematurity, and small for gestational age birth weight. Iron deficiency has a negative effect on intelligence and behavioral development in the infant. It is essential to prevent iron deficiency in the fetus by preventing iron deficiency in the pregnant woman. The requirements for absorbed iron increase during pregnancy from ∼1.0 mg/day in the first trimester to 7.5 mg/day in the third trimester. More than 90% of Scandinavian women of reproductive age have a dietary iron intake below the recommended 15 mg/day. Among nonpregnant women of reproductive age, ∼40% have plasma ferritin ≤30 µg/l, i.e. an unfavorable iron status with respect to pregnancy. An adequate iron status during pregnancy implies body iron reserves ≥500 mg at conception, but only 15-20% of women have iron reserves of such a magnitude. Iron supplements during pregnancy reduce the prevalence of IDA. In Europe, IDA can be prevented by a general low-dose iron prophylaxis of 30-40 mg ferrous iron taken between meals from early pregnancy to delivery. In affluent societies, individual iron prophylaxis tailored by the ferritin concentration should be preferred to general prophylaxis. Suggested guidelines are: ferritin >70 µg/l, no iron supplements; ferritin 31-70 µg/l, 30-40 mg ferrous iron per day, and ferritin ≤30 µg/l, 60-80 mg ferrous iron per day. In women with ferritin <15 µg/l, i.e. depleted iron reserves and possible IDA, therapeutic doses of 100 mg ferrous iron per day should be advised.

Dydrogesterone supplementation in women with threatened preterm delivery--the impact on cytokine profile, hormone profile, and progesterone-induced blocking factor.

Progesterone is indispensable in creating a suitable endometrial environment for implantation, and also for the maintenance of pregnancy. Successful pregnancy depends on an appropriate maternal immune response to the fetus. A protein called progesterone-induced blocking factor (PIBF) acts by inducing Th2-dominant cytokine production to mediate the immunological effects of progesterone. The aim of this prospective study was to compare serum concentrations of progesterone (P), estradiol (E2), anti-inflammatory (IL-10) and pro-inflammatory (IL-6, TNFα, IFNγ) cytokines, and serum PIBF concentrations in women with threatened preterm delivery who were given progesterone supplementation (study group) with those of women with threatened preterm delivery who were not given progesterone supplementation (control group). After dydrogesterone treatment of patients in the study group, serum PIBF as well as progesterone concentrations significantly increased. Women in this group had significantly higher serum levels of IL-10 than controls. The length of gestation was significantly higher in the group of women who were given progesterone supplementation. Our data suggest that dydrogesterone treatment of women at risk of preterm delivery results in increased PIBF production and IL-10 concentrations, and lower concentrations of IFNγ.

Pregnancy associated glycoproteins (PAG) in postpartum cows, ewes, goats and their offspring.

Determination of plasma concentrations of pregnancy associated glycoproteins (PAG) has been used for early pregnancy diagnosis in cows. However, this is complicated by the presence of PAG in plasma for an extended period postpartum. The main objective of the present study was to investigate the postpartum elimination rates of pregnancy associated glycoproteins (PAG) in sheep, goats and cows in order to gain background information applicable to the use of PAG for pregnancy diagnosis in domestic ruminants. A second objective was to investigate whether PAG are transferred to the foetus and newborn, by measuring plasma PAG concentrations in calves, lambs and goat kids before and after colostrum feeding. PAG in the blood at parturition were eliminated by a first order process in the cows and ewes, while a two-step log-linear decline occurred in the goats. Estimated postpartum half-life of plasma PAG in the cows and ewes was 9 and 4.5 days, respectively. In the goats, half-lives were 3.6 and 7.5 days in the initial fast and terminal slow phase. Basal levels were reached 80-90 days postpartum in cows. Plasma PAG concentration can be used for pregnancy diagnosis from day 28 after AI, provided that the time interval from calving to AI is >60 days. Using a heterologous antibody RIA, we found 4 ng/mL to be the appropriate cut-off. Due to the presence of PAG residues from the previous gestation, the interval from AI to pregnancy diagnosis should increase by approximately 0.5 days beyond 28 days for each day of AI closer to calving than 60. Measurements in newborn ruminants suggested that PAG enter the foetal blood in utero and that colostral PAG are transferred to the newborn. Following the peak plasma concentration observed 1 day after birth in most of the animals, PAG were rapidly eliminated in a log-linear fashion.

Dietary determinants of circulating insulin-like growth factor (IGF)-I and IGF binding proteins 1, -2 and -3 in women in the Netherlands.

OBJECTIVE: Epidemiological studies suggest that individuals with elevated plasma concentrations of insulin-like growth factor (IGF-I) are at increased risk of developing cancer. We assessed whether dietary intake of total energy, protein, alcohol, phytoestrogens and related foods, and tomatoes and lycopene was associated with plasma levels of IGF-I and IGF binding proteins (IGFBPs) in Dutch women. METHODS: A cross-sectional study was conducted in 224 premenopausal and 162 postmenopausal women, aged 49-69, participating in the Prospect-EPIC study in the Netherlands. Diet was assessed using a food frequency questionnaire. RESULTS: In postmenopausal women, higher alcohol intake was associated with lower plasma IGFBP-1 concentrations (alcohol 1.4 to 20 g/day: 20% decrease in IGFBP-1; p = 0.04), and higher intake of plant lignans was associated with higher IGFBP-1 concentrations (plant lignans 0 to 1 mg/day: 59% increase in IGFBP-1; p =0.02). Higher soy intake was associated with higher plasma IGFBP-2 concentrations in premenopausal women (soy 0 to 2.5 g/day: 3% increase in IGFBP-2; p = 0.04). No independent associations of dietary factors with IGF-I or IGFBP-3 concentrations were observed. However, in premenopausal women alcohol intake was inversely associated with IGF-I and positively associated with IGFBP-3 after mutual adjustment. CONCLUSIONS: In this study population, with limited variation in dietary intake, total energy, protein, phytoestrogens and lycopene were not associated with IGF-I and IGFBP-3. Alcohol was inversely, and some measures of phytoestrogen intake were positively associated with plasma IGFBP-1 or -2 concentrations. The roles of IGFBP-1 and -2 in relation to IGF-I bioactivity and cancer deserve further investigation.

Vitamin C and E supplementation in women at risk of preeclampsia is associated with changes in indices of oxidative stress and placental function.

OBJECTIVE: We have previously reported a reduced incidence of preeclampsia in women who were at risk and were taking vitamin C (1000 mg/d) and vitamin E (400 IU/d) supplements. In this study, we determined whether supplementation in the same cohort was associated with an improvement in indices of placental dysfunction and oxidative stress toward values determined in women who were at low risk of preeclampsia. STUDY DESIGN: Seventy-nine women who were at high risk and who were taking vitamin supplements and 81 who were taking placebos were compared with 32 women who were at low risk and who were not taking supplements who were studied simultaneously. RESULTS: Indices of oxidative stress and placental function were abnormal in the placebo group. When the placebo group was compared with the women who were at low risk, ascorbic acid, plasminogen activator inhibitor-2, and placenta growth factor concentrations were decreased; and 8-epi-prostaglandin F(2alpha),leptin, and the plasminogen activator inhibitor-1/-2 ratio were increased. In the group that received vitamin supplements, ascorbic acid, 8-epi-prostaglandin F(2alpha), leptin, and plasminogen activator inhibitor-1/-2 values were similar to women who were at low risk. CONCLUSION: Antioxidant supplementation in women who were at risk of preeclampsia was associated with improvement in biochemical indices of the disease.

Placenta growth factor (PlGF) induces vascular endothelial growth factor (VEGF) secretion from mononuclear cells and is co-expressed with VEGF in synovial fluid.

The aims of this study were (i) to determine whether PlGF, VEGF and PlGF/VEGF heterodimers are detected in synovial fluid (SF) and plasma samples from patients with a range of arthropathies; (ii) to describe whether any correlation exists between SF PlGF, VEGF and PlGF/VEGF heterodimer levels and the total and differential SF leucocyte counts; and (iii) to investigate the regulation of peripheral blood mononuclear cell (PBMC) VEGF secretion by stimuli relevant to inflammatory joints. PlGF, VEGF and PlGF/VEGF heterodimer levels were measured in the SF and plasma of patients with a range of arthropathies and normal controls by ELISA. Western blotting for PlGF was performed on SF from three patients with rheumatoid arthritis (RA) and primary inflammatory arthropathies. VEGF was quantified in cell culture supernatants after stimulation with lipopolysaccharide (LPS), PlGF or cobalt ions of PBMC isolated from RA patients and controls. PlGF and VEGF were detected in all SF samples. PlGF/VEGF heterodimers were detected in 10.2% of SF samples, most frequently in RA samples. Western blotting confirmed the presence of PlGF in RA SF. PlGF was detected in 52% of RA and 31% of control plasma samples, and VEGF was detected in 38% of RA and 38% of control plasma samples. PlGF/VEGF heterodimers were detected in 21% of RA samples and none of the control samples. In primary inflammatory arthropathy patients, SF PlGF and VEGF levels correlated significantly with the SF total leucocyte count and the neutrophil count. PlGF was the most potent inducer of PBMC VEGF production in both RA and control subjects. This is the first report of the detection of PlGF and PlGF/VEGF heterodimers in the SF of patients with inflammatory arthropathies, and we have shown for the first time that PlGF up-regulates PBMC VEGF production. PlGF may therefore play a key role in the production of VEGF in the inflammatory joint.

Pregnancy-specific and pregnancy-associated proteins in threatened abortion.

Pregnancy sera (390) were taken between the 5th and 16th weeks of gestation, from subjects whose pregnancies were uneventful throughout the entire gestation period. In-house curves of first-trimester normal values (10th, 50th, 90th percentile) were established for human chorionic gonadotropin (hCG), human placental lactogen (hPL), pregnancy-specific beta 1-glycoprotein (SP-1), pregnancy-associated plasma protein A (PAPP-A), and pregnancy-associated alpha 2-glycoprotein (alpha 2-PAG) after the measurement of these proteins in the sera by immunoassay. Eighty sera from patients with threatened abortion were also obtained and the placental proteins mentioned above were determined. Values falling below the 10th percentile of the normal population were classified as positive (i.e., pathological) results; the others were considered negative. Based on the outcome of the pregnancy, the results were grouped into true positives (low value and lost pregnancy), false positives (low value and ongoing pregnancy), true negatives, and false negatives. The sensitivity, specificity, and the positive predictive value of each protein as an indicator for abortion were calculated. In terms of specificity hCG and SP-1 were good, whilst PAPP-A and hCG showed the highest sensitivity. The best predictive values were obtained from SP-1 and hCG. The results show that PAPP-A and SP-1 perform satisfactorily but that none of these proteins significantly improves on hCG.