Gestation Dependant Changes in Angiogenic Factors and Their Associations with Fetal Growth Measures in Normotensive Pregnancy

Background

Earlier studies indicate that altered angiogenesis at birth is associated with poor birth outcome in women with preeclampsia. Now, we hypothesize that the progressive gestation dependant changes in markers of angiogenesis will be more useful to predict birth weight early even in a normotensive pregnancy. This study for the first time examines the association of gestation dependant changes in the levels of maternal angiogenic factors in addition to their levels in cord with birth weight.

Method

Ninety two pregnant women were followed at three different time points: 16–20 weeks, 26–30 weeks and at delivery during pregnancy. Plasma levels of angiogenic and anti angiogenic factors were determined by commercial enzyme-linked immunosorbent assay (ELISA) kits.

Results

Maternal plasma VEGF levels increased (p<0.01) till the second time point and decreased (p<0.05) up to delivery while plasma sFlt-1 levels increased (p<0.01) at delivery. PlGF levels peaked (p<0.01) at second time point and decreased (p<0.01) at delivery. Cord plasma VEGF levels were higher (p<0.01) and sFlt-1 levels were lower (p<0.01) as compared to maternal values at all time points. Maternal plasma VEGF levels at first time point and PlGF levels at delivery were positively (p<0.05 and p<0.01 respectively), while sFlt-1/PlGF ratio at delivery was negatively associated (p<0.05) with birth weight.

Conclusion

Levels of pro- and anti-angiogenic factors may be differentially regulated across gestation. Maternal VEGF levels at early gestation (16–20 weeks) may be predictive of birth weight in healthy term pregnancies.     

n-6 and n-3 Long-chain polyunsaturated fatty acids in the erythrocyte membrane of Brazilian preterm and term neonates and their mothers at delivery

Placental transfer of the long-chain polyunsaturated fatty acids (LCPUFA) arachidonic (AA) and docosahexaenoic (DHA) acids is selectively high to maintain accretion to fetal tissues, especially the brain. The objectives of the present study were to investigate the essential fatty acid (EFA) and LCPUFA status at birth of preterm and term Brazilian infants and their mothers, from a population of characteristically low intake of n-3 LCPUFA, and to evaluate the association between fetal and maternal status, by the determination of the fatty acid composition of the erythrocyte membrane. Blood samples from umbilical cord of preterm (26-36 weeks of gestation; n = 30) and term (37-42 weeks of gestation; n = 30) infants and the corresponding maternal venous blood were collected at delivery. The LCPUFA composition of the erythrocyte membrane and DHA status were similar for mothers of preterm and term infants. Neonatal AA was higher (P < 0.01) whereas its precursor 18:2n-6 was lower (P < 0.01) than maternal levels, as expected. There was no difference in LCPUFA erythrocyte composition between preterm and term infants, except for DHA. Term infants presented a worse DHA status than preterm infants (P < 0.01) and than their mothers (P < 0.01) at delivery. There was a negative correlation of neonatal DHA with maternal AA and a positive correlation between neonatal AA and maternal AA and 18:2n-6 only at term. These results suggest that the persistent low DHA maternal status, together with the comparatively better AA and 18:2n-6 status, might have affected maternal-fetal transfer of DHA when gestation was completed up to term, and possibly contributed to the worse DHA status of term neonates compared with the preterm neonates.     

Altered PI3-Kinase/Akt Signalling in Skeletal Muscle of Young Men with Low Birth Weight

Background

Low birth weight (LBW) is associated with increased future risk of insulin resistance and type 2 diabetes mellitus. The underlying molecular mechanisms remain poorly understood. We have previously shown that young LBW men have reduced skeletal muscle expression of PI3K p85α regulatory subunit and p110β catalytic subunit, PKCζ and GLUT4 in the fasting state. The aim of this study was to determine whether insulin activation of the PI3K/Akt and MAPK signalling pathways is altered in skeletal muscle of young adult men with LBW.

Methods

Vastus lateralis muscle biopsies were obtained from 20 healthy 19-yr old men with BW</ = 10^th percentile for gestational age (LBW) and 20 normal birth weight controls (NBW), matched for physical fitness and whole-body glucose disposal, prior to (fasting state) and following a 4-hr hyperinsulinemic euglycemic clamp (insulin stimulated state). Expression and phosphorylation of selected proteins was determined by Western blotting.

Principal Findings

Insulin stimulated expression of aPKCζ (p<0.001) and Akt1 (p<0.001) was decreased in muscle of LBW men when compared to insulin stimulated controls. LBW was associated with increased insulin stimulated levels of IRS1 (p<0.05), PI3K p85α (p<0.001) and p110β (p<0.05) subunits, while there was no significant change in these proteins in insulin stimulated control muscle. In addition LBW had reduced insulin stimulated phospho-Akt (Ser 473) (p<0.01), indicative of reduced Akt signalling. Insulin stimulated expression/phosphorylation of all the MAPK proteins studied [p38 MAPK, phospho-p38 MAPK (Thr180/Tyr182), phospho-ERK (Thr 202/Tyr204), JNK1, JNK2 and phospho-JNK (Thr 183/Tyr185)] was not different between groups.

Conclusions

We conclude that altered insulin activation of the PI3K/Akt but not the MAPK pathway precedes and may contribute to development of whole-body insulin resistance and type 2 diabetes in men with LBW.     

Reduced levels of placental long chain polyunsaturated fatty acids in preterm deliveries

Reports suggest that the placenta in preterm birth may provide clues to predicting the risk of individuals developing chronic diseases in later life. Placental delivery of long chain polyunsaturated fatty acids (LCPUFA) (constituents of the cell membrane and precursors of prostaglandins) is essential for the optimal development of the central nervous system of the fetus. The present study examines the levels of LCPUFA and their association with placental weight and birth outcome in 58 women delivering preterm and 44 women delivering at term. Docosahexaenoic acid (DHA) and arachidonic acid (ARA) levels were lower (p<0.01) in women delivering preterm. There was a positive association of placental DHA with placental weight (p=0.036) and nervonic acid with head circumference (p=0.040) in the preterm group. Altered placental LCPUFA status exists in Indian mothers delivering preterm, which may influence the birth outcome.     

Essential fatty acids in erythrocyte phospholipids during pregnancy and at delivery in mothers and their neonates: comparison with plasma phospholipids

Evidence that the essential fatty acid (EFA) status during pregnancy and at birth may not be optimal is mainly based on fatty acid profiles of maternal and neonatal plasma phospholipids. However, erythrocyte phospholipids may be more reliable than plasma phospholipids to reflect the EFA status of an individual. Therefore, the present study compares the levels of EFA and of their derivatives (LCPUFA) in erythrocyte and plasma phospholipids collected during pregnancy and at delivery of 184 women and of their infants at birth. In general, the relative concentrations of erythrocyte and plasma phospholipid fatty acids (% of total fatty acids) were strongly correlated, but not at early pregnancy. The overall changes in fatty acid concentrations during pregnancy were qualitatively comparable between erythrocytes and plasma, although the comparability became less towards the end of pregnancy. The changes in absolute amounts (mg/l) of fatty acids in erythrocyte and plasma phospholipids also compare quite well till 32 weeks of gestation, but not thereafter. Most maternal-neonatal differences in relative fatty acid concentrations are qualitatively comparable for erythrocyte and plasma phospholipids. However, significant differences were observed for the absolute amounts of arachidonic and docosahexaenoic acids. No matter these differences, plasma and erythrocyte phospholipids seem equally suitable to reliably quantify the more functional EFA and LCPUFA status based on fatty acid ratios. Correlations between neonatal and maternal fatty acid values at delivery/birth are highly significant in erythrocyte as well as plasma phospholipids. Neonatal erythrocyte (but not plasma) values also correlated strongly with maternal values at early pregnancy. Therefore, the neonatal EFA and LCPUFA status might be predicted on the basis of EFA and LCPUFA concentrations of maternal erythrocyte phospholipids at early pregnancy.     

Placental Growth Factor for the Prediction of Adverse Outcomes in Patients with Suspected Preeclampsia or Intrauterine Growth Restriction

Background

The circulating concentration of PlGF is reported to be lower in patients experiencing preeclampsia and patients delivering a small for gestational age (SGA) neonate. To evaluate the predictive value of circulating PlGF for preeclampsia and adverse outcome in patients with suspected preeclampsia or intrauterine growth restriction (IUGR).

Methodology/Principal Findings

A double blind prospective study. We enrolled 96 women for suspected preeclampsia or IUGR, and measured plasma levels of PlGF (Triage®) at enrolment. We defined adverse outcome as severe preeclampsia, SGA neonate (<10^th centile) or elective delivery for maternal or fetal complication. Severe adverse outcome was studied among patients included <34 weeks gestation (WG) and defined as eclampsia, HELLP syndrome, very SGA (<3^rd centile) or elective delivery <34 WG. The mean logtransformed PlGF level was lower for women who experienced preeclampsia (2.9 vs 3.7, p = 0.02), and was markedly lower for patients who experienced adverse outcome (2.9 vs 4.3, p<0.001). The odds of presenting an adverse outcome were higher for the lowest tertile of PlGF compared to the higher (OR = 13 , 95% CI [3–50]). For severe adverse outcome, odds were respectively for the lowest and intermediate tertile as compared with the higher tertile : OR = 216, 95% CI [18–2571]; and OR = 17, 95% CI [3–94]. When included <34 WG, patients with a PlGF level <12 pg/ml experienced a severe adverse outcome in 96% of cases (24/25), and only 1 of 20 patients with a PlGF level >5^th centile experienced a severe adverse outcome within 15 days (5%).

Conclusions/Significance

Among women with suspected preeclampsia or IUGR, PlGF helps identify women who will experience an adverse outcome and those who will not within a time period of 15 days.     

A Combined Supplementation of Omega-3 Fatty Acids and Micronutrients (Folic Acid,Vitamin B12) Reduces Oxidative Stress Markers in a Rat Model of Pregnancy Induced Hypertension

Objectives

Our earlier studies have highlighted that an altered one carbon metabolism (vitamin B₁₂, folic acid, and docosahexaenoic acid) is associated with preeclampsia. Preeclampsia is also known to be associated with oxidative stress and inflammation. The current study examines whether maternal folic acid, vitamin B₁₂ and omega-3 fatty acid supplementation given either individually or in combination can ameliorate the oxidative stress markers in a rat model of pregnancy induced hypertension (PIH).

Materials and Methods

Pregnant Wistar rats were assigned to control and five treatment groups: PIH; PIH + vitamin B₁₂; PIH + folic acid; PIH + Omega-3 fatty acids and PIH + combined micronutrient supplementation (vitamin B₁₂ + folic acid + omega-3 fatty acids). L-Nitroarginine methylester (L-NAME; 50 mg/kg body weight/day) was used to induce hypertension during pregnancy. Blood Pressure (BP) was recorded during pregnancy and dams were dissected at d20 of gestation.

Results

Animals from the PIH group demonstrated higher (p<0.01 for both) systolic and diastolic BP; lower (p<0.01) pup weight; higher dam plasma homocysteine (p<0.05) and dam and offspring malondialdehyde (MDA) (p<0.01), lower (p<0.05) placental and offspring liver DHA and higher (p<0.01) tumor necrosis factor–alpha (TNF–ά) levels as compared to control. Individual micronutrient supplementation did not offer much benefit. In contrast, combined supplementation lowered systolic BP, homocysteine, MDA and placental TNF-ά levels in dams and liver MDA and protein carbonyl in the offspring as compared to PIH group.

Conclusion

Key constituents of one carbon cycle (folic acid, vitamin B₁₂ and DHA) may play a role in reducing oxidative stress and inflammation in preeclampsia.     

Maternal BMI Associations with Maternal and Cord Blood Vitamin D Levels in a North American Subset of Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study Participants

ObjectiveObesity in pregnancy may be associated with reduced placental transfer of 25-hydroxyvitamin D (25-OHD). The objective of this study was to examine associations between maternal BMI and maternal and cord blood levels of 25-OHD in full term neonates born to a single racial cohort residing at similar latitude. Secondary objectives were to examine associations between maternal glucose tolerance with maternal levels of 25-OHD and the relationship between cord blood 25-OHD levels and neonatal size.MethodsThis study was conducted among participants of the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) Study meeting the following criteria: residing at latitudes 41–43°, maternal white race, and gestational age 39–41 weeks. Healthy pregnant women underwent measures of height, weight, and a 75-g fasting oral glucose tolerance test (OGTT) at approximately 28 weeks gestation. Maternal and cord blood sera were analyzed for total 25-OHD by HPLC tandem mass spectrometry. Statistical analyses included ANOVA and linear regression models.ResultsMaternal and cord blood (N = 360) mean levels (sd) of 25-OHD were 37.2 (11.2) and 23.4 (9.2) ng/ml, respectively, and these levels were significantly different among the 3 field centers (ANOVA p< 0.001). Maternal serum 25-OHD was lower by 0.40 ng/ml for BMI higher by 1 kg/m² (p<0.001) in an adjusted model. Maternal fasting plasma glucose, insulin sensitivity, and presence of GDM were not associated with maternal serum 25-OHD level when adjusted for maternal BMI. Cord blood 25-OHD was lower by 0.26 ng/ml for maternal BMI higher by 1 kg/m² (p<0.004). With adjustment for maternal age, field center, birth season and maternal serum 25-OHD, the association of cord blood 25-OHD with maternal BMI was attenuated. Neither birth weight nor neonatal adiposity was significantly associated with cord blood 25-OHD levels.ConclusionThese results suggest that maternal levels of 25-OHD are associated with maternal BMI. The results also suggest that interpretation of neonatal 25-OHD levels may need to incorporate specific maternal factors in addition to season of birth and latitude.     

High Levels of Both n-3 and n-6 Long-Chain Polyunsaturated Fatty Acids in Cord Serum Phospholipids Predict Allergy Development

Background

Long-chain polyunsaturated fatty acids (LCPUFAs) reduce T-cell activation and dampen inflammation. They might thereby counteract the neonatal immune activation and hamper normal tolerance development to harmless environmental antigens. We investigated whether fatty acid composition of cord serum phospholipids affects allergy development up to age 13 years.

Methods

From a population-based birth-cohort born in 1996/7 and followed until 13 years of age (n = 794), we selected cases with atopic eczema (n = 37) or respiratory allergy (n = 44), as well as non-allergic non-sensitized controls (n = 48) based on diagnosis at 13 years of age. Cord and maternal sera obtained at delivery from cases and controls were analysed for proportions of saturated, monounsaturated and polyunsaturated fatty acids among serum phospholipids.

Results

The cord serum phospholipids from subject who later developed either respiratory allergy or atopic eczema had significantly higher proportions of 5/8 LCPUFA species, as well as total n-3 LCPUFA, total n-6 LCPUFA and total LCPUFA compared to cord serum phospholipids from controls who did not develop allergy (P<0.001 for all comparisons). Conversely, individuals later developing allergy had lower proportion of the monounsaturated fatty acid 18∶1n-9 as well as total MUFA (p<0.001) among cord serum phospholipids. The risk of respiratory allergy at age 13 increased linearly with the proportion of n-3 LCPUFA (P_trend<0.001), n-6 LCPUFA (P_trend = 0.001), and total LCPUFA (P_trend<0.001) and decreased linearly with the proportions of total MUFA (P_trend = 0.025) in cord serum phospholipids. Furthermore, Kaplan-Meier estimates of allergy development demonstrated that total LCPUFA proportion in cord serum phospholipids was significantly associated with respiratory allergy (P = 0.008) and sensitization (P = 0.002), after control for sex and parental allergy.

Conclusion

A high proportion of long-chain PUFAs among cord serum phospholipids may predispose to allergy development. The mechanism is unknown, but may involve dampening of the physiologic immune activation in infancy needed for proper maturation of the infant''s immune system.     

Association between Cytomegalovirus Antibody Levels and Cognitive Functioning in Non-Elderly Adults

Background

Elevated levels of antibodies to Cytomegalovirus (CMV) have been associated with cognitive impairment, but the quantitative relationship between CMV antibody levels and domains of cognitive functioning in younger adults has not been established.

Methods

We measured IgG class antibodies to Cytomegalovirus in 521 individuals, mean age 32.8 years. Participants were selected for the absence of psychiatric disorder and of a serious medical condition that could affect brain functioning. Cognitive functioning was measured with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the Wisconsin Card Sorting Test, Trail Making Test part A, and the WAIS III Letter Number Sequencing subtest. Linear regression analyses were used to measure the quantitative association between cognitive scores and Cytomegalovirus IgG antibody level. Logistic regression analyses were used to measure the odds of low cognitive scores and elevated antibody levels defined as an antibody level > = 50^th, 75^th, and 90^th percentile of the group.

Results

Higher levels of CMV antibodies were associated with lower performance on RBANS Total (coefficient −1.03, p<.0002), Delayed Memory (coefficient −0.94, p<.001), Visuospatial/Constructional (coefficient −1.77, p<5×10⁻⁷), and Letter Number Sequencing (coefficient −0.15, p<.03). There was an incremental relationship between the level of CMV antibody elevation and the odds of a low RBANS Total score. The odds of a low total cognitive score were 1.63 (95^th % CI 1.01, 2.64; p<.045), 2.22 (95^th % CI 1.33, 3.70; p<.002), and 2.46 (95^th % CI 1.24, 4.86; p<.010) with a CMV antibody level greater than or equal to the 50^th, 75^th, and 90^th percentile respectively.

Conclusions

Higher levels of Cytomegalovirus antibodies are associated with lower levels of cognitive functioning in non-elderly adults. Methods for the prevention and treatment of CMV infection should be evaluated to determine if they result in an improvement in cognitive functioning in otherwise healthy adults.     

Correlations between blood and tissue omega-3 LCPUFA status following dietary ALA intervention in rats

The aim of this study was to assess relationships between the fatty acid contents of plasma and erythrocyte phospholipids and those in liver, heart, brain, kidney and quadriceps muscle in rats. To obtain a wide range of tissue omega-3 (n-3) long chain polyunsaturated fatty acids (LCPUFA) we subjected weanling rats to dietary treatment with the n-3 LCPUFA precursor, alpha linolenic acid (ALA, 18:3 n-3) for 3 weeks. With the exception of the brain, we found strong and consistent correlations between the total n-3 LCPUFA fatty acid content of both plasma and erythrocyte phospholipids with fatty acid levels in all tissues. The relationships between eicosapentaenoic acid (EPA, 20:5 n-3) and docosapentaenoic acid (DPA, 22:5 n-3) content in both blood fractions with levels in liver, kidney, heart and quadriceps muscle phospholipids were stronger than those for docosahexaenoic acid (DHA, 22:6 n-3). The strong correlations between the EPA+DHA (the Omega-3 Index), total n-3 LCPUFA and total n-3 PUFA contents in both plasma and erythrocyte phospholipids and tissues investigated in this study suggest that, under a wide range of n-3 LCPUFA values, plasma and erythrocyte n-3 fatty acid content reflect not only dietary PUFA intakes but also accumulation of endogenously synthesised n-3 LCPUFA, and thus can be used as a reliable surrogate for assessing n-3 status in key peripheral tissues.     

Reduced placental docosahexaenoic acid levels associated with increased levels of sFlt-1 in preeclampsia

Our earlier studies, in preeclamptic women have shown altered levels of long chain polyunsaturated fatty acids (LCPUFA), essential constituents of the cell membrane lipids responsible for membrane stability as one of the key factors contributing to the pathophysiology of preeclampsia. We have also reported elevated levels of sFlt-1 in preeclampsia. The present study examines the levels of LCPUFA and their association with sFlt-1 levels in 69 pre-eclamptic women and 40 normotensive women. DHA and omega 3 fatty acid levels were lower (p<0.001) while arachidonic acid and omega 6 fatty acid levels were higher (p<0.05) in preeclamptic women as compared to normotensive women. Maternal plasma sFlt-1 levels were higher (p<0.05) in preeclamptic women and were negatively associated with DHA (p=0.008) and omega 3 fatty acids concentrations (p=0.031). Our results suggest that altered placental LCPUFA may result in altered membrane lipid fatty acid composition leading to increased release of sFlt-1 in circulation.     

Association between Low Levels of Mannan-Binding Lectin and Markers of Autoimmune Thyroid Disease in Pregnancy

Functional deficiency of mannan-binding lectin (MBL) has been associated with adverse pregnancy outcome. Adverse events during pregnancy have also been described in women with autoimmune thyroid diseases (AITD), and thyroid hormones have been shown to influence serum levels of MBL. Therefore, the aim of this study was to analyse the impact of MBL-deficiency on the outcome of pregnancy in relation to the presence of AITD. Almost one year after delivery, we assessed serum MBL levels and MBL2-genotypes in 212 women positively screened for AITD in pregnancy. In 103 of these women, we could also measure MBL levels in frozen serum samples from the 9-12^th gestational week, obtaining 96 pairs of MBL values (pregnancy vs. follow-up). As controls, 80 sera of pregnant women screened negatively for AITD were used. MBL2-genotyping was performed using multiplex PCR. Women with thyroid dysfunction and/or thyroid peroxidase antibodies (TPOAb) had lower MBL levels during pregnancy than controls, (3275 vs. 5000 ng/ml, p<0.05). The lowest levels were found in women with elevated thyroid-stimulating hormone (TSH) levels in the absence of TPOAb (2207 ng/ml; p<0.01 as compared to controls). MBL2 genotype distribution did not differ between subgroups. At a median follow-up period of 17 months (range: 3–78 months) after delivery, median MBL level had decreased further to 1923 ng/ml (p<0.0001) without significant changes in TSH. In an explorative survey, functional MBL-deficiency was neither linked to a history of spontaneous abortion, nor other obstetric complications, severe infections throughout life/pregnancy or antibiotics use in pregnancy. In conclusion, hypothyroidism during pregnancy is associated with decreased MBL levels, and the levels decreased further after delivery.     

Distinct Disease Phases in Muscles of Facioscapulohumeral Dystrophy Patients Identified by MR Detected Fat Infiltration

Facioscapulohumeral muscular dystrophy (FSHD) is an untreatable disease, characterized by asymmetric progressive weakness of skeletal muscle with fatty infiltration. Although the main genetic defect has been uncovered, the downstream mechanisms causing FSHD are not understood. The objective of this study was to determine natural disease state and progression in muscles of FSHD patients and to establish diagnostic biomarkers by quantitative MRI of fat infiltration and phosphorylated metabolites. MRI was performed at 3T with dedicated coils on legs of 41 patients (28 men/13 women, age 34–76 years), of which eleven were re-examined after four months of usual care. Muscular fat fraction was determined with multi spin-echo and T1 weighted MRI, edema by TIRM and phosphorylated metabolites by 3D ³¹P MR spectroscopic imaging. Fat fractions were compared to clinical severity, muscle force, age, edema and phosphocreatine (PCr)/ATP. Longitudinal intramuscular fat fraction variation was analyzed by linear regression. Increased intramuscular fat correlated with age (p<0.05), FSHD severity score (p<0.0001), inversely with muscle strength (p<0.0001), and also occurred sub-clinically. Muscles were nearly dichotomously divided in those with high and with low fat fraction, with only 13% having an intermediate fat fraction. The intramuscular fat fraction along the muscle’s length, increased from proximal to distal. This fat gradient was the steepest for intermediate fat infiltrated muscles (0.07±0.01/cm, p<0.001). Leg muscles in this intermediate phase showed a decreased PCr/ATP (p<0.05) and the fastest increase in fatty infiltration over time (0.18±0.15/year, p<0.001), which correlated with initial edema (p<0.01), if present. Thus, in the MR assessment of fat infiltration as biomarker for diseased muscles, the intramuscular fat distribution needs to be taken into account. Our results indicate that healthy individual leg muscles become diseased by entering a progressive phase with distal fat infiltration and altered energy metabolite levels. Fat replacement then relatively rapidly spreads over the whole muscle.     

Delay of preterm delivery in sheep by omega-3 long-chain polyunsaturates

A positive correlation has been shown between dietary intake of long-chain omega-3 fatty acids in late pregnancy and gestation length in pregnant women and experimental animals. To determine whether omega-3 fatty acids have an effect on preterm labor in sheep, a fish oil concentrate emulsion was continuously infused to six pregnant ewes from 124 days gestational age. At 125 days, betamethasone was administered to the fetus to produce preterm labor. Both the onset of labor and the time of delivery were delayed by the fish oil emulsion. Two of the omega-3-infused ewes reverted from contractions to nonlabor, an effect never previously observed for experimental glucocorticoid-induced preterm labor in sheep. Maternal plasma estradiol and maternal and fetal prostaglandin E2 rose in control ewes but not in those infused with omega-3 fatty acid. The ability of omega-3 fatty acids to delay premature delivery in sheep indicates their possible use as tocolytics in humans. Premature labor is the major cause of neonatal death and long-term disability, and these studies present information that may lead to a novel therapeutic regimen for the prevention of preterm delivery in human pregnancy.     

Effects of Acute Supramaximal Cycle Exercise on Plasma FFA Concentration in Obese Adolescent Boys

Aims

The aims of the present study are 1) to evaluate the free fatty acid (FFA) profile and 2) to determine the relative anaerobic and aerobic contributions to total energy consumption during repeated supramaximal cycling bouts (SCE) in adolescent boys with different body weight statuses.

Materials and Methods

Normal-weight (NW), overweight (OW), and obese (OB) adolescent boys (n =15 per group) completed a SCE sessions consisted of 6 x 6s maximal sprints with 2 min of passive rest between each repetition. Plasma FFA levels were determined at rest, immediately after a 10 min warm-up, and immediately at the end of SCE. The anaerobic and aerobic contributions (%) were measured via repeated SCE bouts. Insulin resistance was calculated using the homoeostatic model assessment (HOMA-IR) index.

Results

The FFA concentrations measured immediately after SCE were higher in the OB group than in the OW and NW (p<0.01 and p<0.01, respectively) groups. Moreover, the anaerobic contributions to SCE were significantly lower in obese adolescents (p<0.01) and decreased significantly during the 2^nd, 3^rd and 4^th repetitions. The FFA levels were significantly associated with the HOMA-IR index and aerobic contribution among adolescent boys (r=0.83 and r=0.91, respectively, p<0.01).

Conclusion

In contrast to the NW and OW groups, there is an increase in lipid mobilization and sift to aerobic energy metabolism during SCE in the OB group.     

Circulating MicroRNAs in Maternal Blood as Potential Biomarkers for Fetal Hypoxia In-Utero

Stillbirth affects 1 in 200 pregnancies and commonly arises due to a lack of oxygen supply to the fetus. Current tests to detect fetal hypoxia in-utero lack the sensitivity to identify many babies at risk. Emerging evidence suggests that microRNAs derived from the placenta circulate in the maternal blood during pregnancy and may serve as non-invasive biomarkers for pregnancy complications. In this study, we examined the expression of miRs known to be regulated by hypoxia in two clinical settings of significant fetal hypoxia: 1) labour and 2) fetal growth restriction. Six miRs (miR 210, miR 21, miR 424, miR 199a, miR 20b, and miR 373) were differentially expressed in pregnancies complicated by fetal hypoxia. In healthy term pregnancies there was a 4.2 fold increase in miR 210 (p<0.01), 2.7 fold increase in miR 424 (p<0.05), 2.6 fold increase in miR 199a (p<0.01) and 2.3 fold increase in miR 20b (p<0.05) from prior to labour to delivery of the fetus. Furthermore, the combined expression of miR 21 and miR 20b correlated with the degree of fetal hypoxia at birth determined by umbilical cord lactate delivery (r = 0.79, p = 0.03). In pregnancies complicated by severe preterm fetal growth restriction there was upregulation of the hypoxia-regulated miRs compared to gestation-matched controls: 3.6 fold in miR 210 (p<0.01), 3.6 fold in miR 424 (p<0.05), 5.9 fold in miR 21 (p<0.01), 3.8 fold in miR 199a (p<0.01) and 3.7 fold in miR 20b (p<0.01). Interestingly, the expression of miR 373 in gestation matched controls was very low, but was very highly expressed in FGR (p<0.0001). Furthermore, the expression increased in keeping with the degree of in-utero hypoxia estimated by fetal Doppler velocimetry. We conclude quantifying hypoxia-regulated miRs in the maternal blood may identify pregnancies at risk of fetal hypoxia, enabling early intervention to improve perinatal outcomes.     

Maternal dietary omega-3 fatty acid intake increases resolvin and protectin levels in the rat placenta

Placental inflammation is associated with several pregnancy disorders. Inflammation is limited by anti-inflammatory and proresolving mechanisms, the latter partly mediated by resolvins and protectins derived from omega-3 polyunsaturated fatty acids (n-3PUFA). We examined effects of dietary n-3PUFAs on levels of resolvins, protectins, and lipoxygenase (ALOX) enzymes in the rat placenta. Rats consumed standard (Std) or high n-3PUFA (Hn3) diets from day 1 of pregnancy; tissues were collected on day 17 or 22 (term = day 23). Maternal Hn3 diet increased resolvin and protectin precursors, 18R/S-HEPE (P < 0.001), and 17R/S-HDHA (P < 0.01) at both days. Resolvins (17R-RvD1 and RvD1) increased at day 22 (P < 0.001) after Hn3 consumption, coincident with higher Alox15b and Alox5 mRNA expression, while RvD2 increased at both days (P < 0.05). Protectins, PD1, and 10S,17S-DiHDHA increased over late gestation (P < 0.001), coincident with higher Alox15 mRNA expression (P < 0.001) and further increased with Hn3 diet (P < 0.05). Maternal systemic and placental proinflammatory mediators were not suppressed by Hn3 diet; systemic IL1β, placental Il1β, and Il6 mRNA expression increased marginally with Hn3 at day 22 (P < 0.001), while Ptgs1 (Cox1) expression increased both days (P < 0.05). Our data indicate that maternal n-3PUFA supplementation enhances expression of enzymes in the n-3PUFA metabolic pathway and increases placental levels of resolvins and protectins.     

Modification of Epigenetic Patterns in Low Birth Weight Children: Importance of Hypomethylation of the ACE Gene Promoter

There is a growing body of evidence that epigenetic alterations are involved in the pathological mechanisms of many chronic disorders linked to fetal programming. Angiotensin-converting enzyme (ACE) appears as one candidate gene that brings new insights into the epigenetic control and later development of diseases. In this view, we have postulated that epigenetic modifications in the ACE gene might show different interactions between birth weight (BW), blood pressure levels, plasma ACE activity and ACE I/D polymorphism. To explore this hypothesis, we performed a cross-sectional study to evaluate the DNA methylation of 3 CpG sites using pyrosequencing within the ACE gene promoter of peripheral blood leukocytes from 45 LBW children compared with 70 NBW children. Our results have revealed that LBW children have lower methylation levels (P<0.001) in parallel with a higher ACE activity (P = 0.001). Adjusting for prematurity, gender, age, body mass index, and family history of cardiovascular disease did not alter these findings. We have also performed analyses of individual CpG sites. The frequency of DNA methylation was significantly different at two CpG sites (site 1: nucleotide position +555; and site 3: nucleotide position +563). In addition, we have found a significant inverse correlation between degree of DNA methylation and both ACE activity (P<0.001) and systolic blood pressure levels (P<0.001). We also observed that the methylation level was significantly lower in LBW children who are carriers of the DD genotype compared to NBW children with DD genotype (P<0.024). In conclusion, we are able to demonstrate that the hypomethylation in the 3 CpG sites of ACE gene promoter is associated with LBW in 6 to 12 year-old children. The magnitude of these epigenetic changes appears to be clinically important, which is supported by the observation that discrete changes in DNA methylation can affect systolic blood pressure and ACE protein activity levels.     

Plasma Concentrations of Soluble Endoglin versus Standard Evaluation in Patients with Suspected Preeclampsia

Background

The purpose of this study was to compare plasma soluble endoglin (sEng) levels with standard clinical evaluation or plasma levels of other angiogenic proteins [soluble fms-like tyrosine kinase 1 (sFlt1) and placental growth factor (PlGF)] in predicting short-term adverse maternal and perinatal outcomes in women with suspected preeclampsia presenting prior to 34 weeks.

Methods and Findings

Data from all women presenting at <34 weeks for evaluation of preeclampsia with singleton pregnancies (July 2009−October 2010) were included in this analysis and sEng levels were measured at presentation. Data was analyzed for 170 triage encounters and presented as median {25−75^th centile}. Thirty-three percent of patients (56 of 170) experienced an adverse outcome. sEng levels (ng/ml) were significantly elevated in patients who subsequently experienced adverse outcomes compared to those who did not (32.3 {18.1, 55.8} vs 4.8 {3.2, 8.6}, p<0.0001). At a 10% false positive rate, sEng had higher detection rates of adverse outcomes than the combination of highest systolic blood pressure, proteinuria and abnormal laboratory tests (80.4 {70.0, 90.8} vs 63.8 {51.4, 76.2}, respectively). Subjects in the highest quartile of sEng were more likely to deliver early compared to those in the lowest quartile (HR: 14.96 95% CI: 8.73−25.62, p<0.0001). Natural log transformed sEng correlated positively with log sFlt1 levels (r = 0.87) and inversely with log PlGF levels (r = −0.79) (p<0.0001 for both). Plasma sEng had comparable area under the curve for prediction of adverse outcomes as measurement of sFlt1/PlGF ratio (0.88 {0.81, 0.95} for sEng versus 0.89 {0.83, 0.95} for sFlt1/PlGF ratio, p = 0.74).

Conclusions

In women with suspected preeclampsia presenting prior to 34 weeks of gestation, sEng performs better than standard clinical evaluation in detecting adverse maternal and fetal outcomes occurring within two weeks of presentation. Soluble endoglin was strongly correlated with sFlt1 and PlGF levels, suggesting common pathogenic pathways leading to preeclampsia.