Maternal supplementation of curcumin-olive oil nanocomposite improves uteroplacental blood flow, placental growth and antioxidant capacity in goats.

This experiment was designed to investigate the impact of curcumin-olive oil nanocomposite (CONC) supplementation on uteroplacental hemodynamics and ultrasonographic measurements as well as maternal oxidative status in midgestating goats. Twelve synchronized pregnant goats (85.58 ± 1.08 days of gestation; mean ± SD) were uniformly assigned to two groups (n = 6/group); the first group received daily oral supplementation of CONC (3 mg/kg body weight; nanocurcumin [NC] group) for 32 days, and the second group was offered physiological saline (control) following the NC group timeline. The goats of both groups were examined at 3-day intervals for middle uterine (MUA) and umbilical (UMA) arteries hemodynamics (pulsatility index [PI], resistive index [RI], systole/diastole [S/D] and blood flow rate [BFR]) and diameters, uteroplacental thickness (UPT), placentomes' diameter (PD) and echogenicity, steroid hormones (progesterone and estradiol 17ß), oxidative biomarkers (total antioxidant capacity [TAC], catalase [CAT], malondialdehyde [MDA]), nitric oxide (NO) and blood cells DNA integrity. The UPT (p = 0.012) and PD (p = 0.021) values were higher in the NC group than in their counterparts' control group (D11-32). There were increases in diameter (p = 0.021 and p = 0.012) and decreases (p = 0.021, p = 0.016 and p = 0.041 [MUA]; p = 0.015, p = 0.023 and p = 0.011 [UMA] respectively) in Doppler indices (PI, RI and S/D) of the MUA and UMA in the NC group compared to the control group (D14-32). On D20-32 (MUA) and D14-32 (UMA), the NC goats had higher BFR than the control group (p = 0.021, 0.018 respectively). The means of blood cells with fragmented DNA were lower (p = 0.022) in the NC group than in the control group on Days 8 and 21 postsupplementation. There were increases in CAT and NO (D20-32; p = 0.022 and p = 0.004 respectively), and TAC (D17-32; p = 0.007) levels in the NC goats compared to the control ones. The NC group had lower (p = 0.029) concentrations of MDA than the control group on Day 20 postsupplementation onward. In conclusion, oral supplementation of CONC improved uteroplacental blood flow and the antioxidant capacity of midgestating goats.

Human Milk Oligosaccharides in Cord Blood Are Altered in Gestational Diabetes and Stimulate Feto-Placental Angiogenesis In Vitro.

(1) Background: Human milk oligosaccharides (HMOs) are present in maternal serum during pregnancy and their composition is altered in gestational diabetes (GDM). HMOs are also in fetal cord blood and in contact with the feto-placental endothelium, potentially affecting its functions, such as angiogenesis. We hypothesized that cord blood HMOs are changed in GDM and contribute to increased feto-placental angiogenesis, hallmark of GDM. (2) Methods: Using HPLC, we quantified HMOs in cord blood of women with normal glucose tolerance (NGT, n = 25) or GDM (n = 26). We investigated in vitro angiogenesis using primary feto-placental endothelial cells (fpECs) from term placentas after healthy pregnancy (n = 10), in presence or absence of HMOs (100 µg/mL) isolated from human milk, 3'-sialyllactose (3'SL, 30 µg/mL) and lactose (glycan control) and determined network formation (Matrigel assay), proliferation (MTT assays), actin organization (F-actin staining), tube formation (fibrin tube formation assay) and sprouting (spheroid sprouting assay). (3) Results: 3'SL was higher in GDM cord blood. HMOs increased network formation, HMOs and 3'SL increased proliferation and F-actin staining. In fibrin assays, HMOs and 3'SL increased total tube length by 24% and 25% (p < 0.05), in spheroid assays, by 32% (p < 0.05) and 21% (p = 0.056), respectively. Lactose had no effect. (4) Conclusions: Our study suggests a novel role of HMOs in feto-placental angiogenesis and indicates a contribution of HMO composition to altered feto-placental vascularization in GDM.

Blocking Placental Class G Immunoglobulin Transfer Prevents NMDA Receptor Antibody Effects in Newborn Mice.

BACKGROUND AND OBJECTIVES: To determine in a mouse model whether neonatal Fc receptor (FcRn) blockade prevents the placental transfer of class G immunoglobulin (IgG) derived from patients with anti-NMDA receptor (NMDAR) encephalitis and their pathogenic effects on the fetuses and offspring. METHODS: Pregnant C57BL/6J mice were administered via tail vein FcRn antibody (FcRn-ab) or saline solution 6 hours before administration of patients' or controls' IgG on days 14, 15, and 16 of gestation. Three experimental groups were established: mice receiving controls' IgG, patients' IgG, or patients' IgG along with pretreatment with FcRn-ab. Immunohistochemical staining, confocal microscopy, hippocampal long-term potentiation, and standardized developmental and behavioral tasks were used to assess the efficacy of treatment with FcRn-ab. RESULTS: In pregnant mice that received patients' IgG, treatment with FcRn-ab prevented the IgG from reaching the fetal brain, abrogating the decrease of NMDAR clusters and the reduction of cortical plate thickness that were observed in fetuses from untreated pregnant mice. Moreover, among the offspring of mothers that received patients' IgG, those whose mothers were treated with FcRn-ab did not develop the alterations that occurred in offspring of untreated mothers, including impairment in hippocampal plasticity, delay in innate reflexes, and visuospatial memory deficits. DISCUSSION: FcRn blockade prevents placental transfer of IgG from patients with anti-NMDAR encephalitis and abrogates the synaptic and neurodevelopmental alterations caused by patients' antibodies. This model has potential therapeutic implications for other antibody-mediated diseases of the CNS during pregnancy.

Pregnancy-related pharmacokinetics and antimicrobial prophylaxis during fetal surgery, cefazolin and clindamycin as examples.

Antimicrobial prophylaxis during surgery aims to prevent post-operative site infections. For fetal surgery, this includes the fetal and amniotic compartments. Both are deep compartments as drug equilibrium with maternal blood is achieved relatively late. Despite prophylaxis, chorio-amnionitis or endometritis following ex utero intrapartum treatment or fetoscopy occur in 4.13% and 1.45% respectively of the interventions. This review summarizes the observations on two commonly administered antimicrobials (cefazolin, clindamycin) for surgical prophylaxis during pregnancy, with emphasis on the deep compartments. For both compounds, antimicrobial exposure is on target when we consider the maternal and fetal plasma compartment. In contrast, amniotic fluid concentrations-time profiles display a delayed and much more blunted pattern, behaving as deep compartment. For cefazolin, there are data that document further dilution in the setting of polyhydramnios. Along this deep compartment concept, there is some accumulation during repeated administration, modeled for cefazolin and observed for clindamycin. The relative underexposure to antimicrobials in amniotic fluid may be reflected in the pattern of maternal-fetal complications after fetal surgery, and suggest that antimicrobial prophylaxis practices for fetal surgery should be reconsidered. Further studies should be designed by a multidisciplinary team (fetal surgeons, clinical pharmacologists and microbiologists) to facilitate efficient evaluation of antimicrobial prophylaxis.

Carbon monoxide increases utero-placental angiogenesis without impacting pregnancy specific adaptations in mice.

BACKGROUND: Cigarette smokers have a reduced risk of developing preeclampsia, possibly attributed to an increase in carbon monoxide (CO) levels. Carbon monoxide is a gasotransmitter that has been implicated in maintaining vascular tone, increasing angiogenesis, and reducing inflammation and apoptosis at physiological concentrations. Moderately increasing CO concentrations may have therapeutic potential to prevent or treat preeclampsia; however, the effects of CO on pregnancy are under studied. Our objective was to investigate the effect of CO on major angiogenic and inflammatory markers in pregnancy, and to evaluate the effect of CO on indicators of placental health. FINDINGS: Pregnant CD-1 mice were constantly exposed to either ambient air or 250 ppm CO from conception until gestation day (GD)10.5 or GD16.5. Using a qRT-PCR array, we identified that CO increased expression of major angiogenic genes at the implantation site on GD10.5, but not GD16.5. Pro-inflammatory cytokines in the plasma and tissue lysates from implantation sites in treated mice were not significantly different compared to controls. Additionally, CO did not alter the implantation site phenotype, in terms of proliferative capacity, invasiveness of trophoblasts, or abundance of uterine natural killer cells. CONCLUSIONS: This study suggests that CO exposure is pro-angiogenic at the maternal-fetal interface, and is not associated with demonstrable concerns during murine pregnancy. Future studies are required to validate safety and efficacy of CO as a potential therapeutic for vascular insufficiency diseases such as preeclampsia and intrauterine growth restriction.

Increased uterine artery blood flow in hypoxic murine pregnancy is not sufficient to prevent fetal growth restriction†.

Incomplete maternal vascular responses to pregnancy contribute to pregnancy complications including intrauterine growth restriction (IUGR) and preeclampsia. We aimed to characterize maternal vascular dysfunction in a murine model of fetal growth restriction as an approach toward identifying targetable pathways for improving pregnancy outcomes. We utilized a murine model of late-gestation hypoxia-induced IUGR that reduced E18.5 fetal weight by 34%. Contrary to our hypothesis, uterine artery blood flow as measured in vivo by Doppler ultrasound was increased in mice housed under hypobaric hypoxia (385 mmHg; 5500 m) vs normoxia (760 mmHg; 0 m). Using wire myography, uterine arteries isolated from hypoxic mice had similar vasodilator responses to the two activators A769662 and acetylcholine as those from normoxic mice, although the contribution of an increase in nitric oxide production to uterine artery vasodilation was reduced in the hypoxic vs normoxic groups. Vasoconstrictor responses to phenylephrine and potassium chloride were unaltered by hypoxia. The levels of activated adenosine monophosphate-activated protein kinase (AMPK) were reduced with hypoxia in both the uterine artery and placenta as measured by western blot and immunohistochemistry. We concluded that the rise in uterine artery blood flow may be compensatory to hypoxia but was not sufficient to prevent fetal growth restriction. Although AMPK signaling was reduced by hypoxia, AMPK was still receptive to pharmacologic activation in the uterine arteries in which it was a potent vasodilator. Thus, AMPK activation may represent a new therapy for pregnancy complications involving reduced uteroplacental perfusion.

Reconciling the distinct roles of angiogenic/anti-angiogenic factors in the placenta and maternal circulation of normal and pathological pregnancies.

A branched vascular network is crucial to placental development and is dependent on factors such as vascular endothelial growth factor (VEGF), placental growth factor (PlGF), angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), soluble fms-like tyrosine kinase-1 (sFlt-1) and soluble endoglin (sEng) to regulate blood vessel growth. Imbalances in these factors can lead to aberrant placental vascular development. Throughout pregnancy, these factors are also released into the maternal circulation to aid in adapting the maternal cardiovascular system to pregnancy. Increased secretion of anti-angiogenic factors can lead to the development of an anti-angiogenic state in the mother and contribute to the development of pregnancy pathologies such as pre-eclampsia and foetal growth restriction (FGR). Thus, what are commonly referred to as 'angiogenic factors' have distinct functions in the maternal and placental circulations making this a misnomer. Indeed, technical issues in this field such as assay methodology and lack of data considering different placental cell types mean that the physiological roles of these factors in the maternal and placental circulations are frequently muddled in the literature. This review aims to (1) unpick the distinct roles of factors that influence placental vascular development and separate these from the roles of the same factors within the maternal circulation in normal pregnancy and (2) critically assess how imbalances may contribute to the distinct pathophysiological mechanisms underlying pregnancy disorders. Together, this critical assessment of the field endeavours to improve our ability to accurately use these factors as predictive/diagnostic biomarkers in the future.

Anti-inflammatory Action of Metformin with Respect to CX3CL1/CX3CR1 Signaling in Human Placental Circulation in Normal-Glucose Versus High-Glucose Environments.

Upregulation of chemokine CX3CL1 and its receptor CX3CR1 occurs in the diabetic human placenta. Metformin, an insulin-sensitizing biguanide, is used in the therapy of diabetic pregnancy. By preventing the activation of NF-κB, metformin exhibits anti-inflammatory properties. We examined the influence of hyperglycemia (25 mmol/L glucose; HG group; N = 36) on metformin-mediated effects on CX3CL1 and TNF-α production by placental lobules perfused extracorporeally. Additionally, CX3CR1 expression and contents of CX3CR1, TNF-α receptor 1 (TNFR1), and NF-κB proteins in the placental tissue were evaluated. Placentae perfused under normoglycemia (5 mmol/L glucose; NG group; N = 36) served as the control. Metformin (2.5 and 5.0 mg/L; subgroups B and C) lowered the production of CX3CL1 and TNF-α in a dose-dependent and time-dependent manner. Hyperglycemia did not weaken the strength of these metformin effects. Moreover, CX3CL1 levels after perfusion with 5.0 mg/L metformin were reduced by 33.28 and 33.83% (at 120 and 150 min, respectively) in the HG-C subgroup versus 24.98 and 23.66% in the NG-C subgroup, which indicated an augmentation of the metformin action over time in hyperglycemia. CX3CR1 expression was significantly higher in the HG-B and HG-C subgroups compared to that in the NG-B and NG-C subgroups. Increased CX3CR1 protein content in the placental lysates was observed in subgroups B and C. The two higher metformin concentrations significantly decreased the levels of NF-κBp65 protein content in both groups. However, the decrease was significantly stronger in hyperglycemia. TNFR1 upregulation in the HG group was not affected by metformin. Further studies on metformin therapy during pregnancy are needed, including safety issues.

HIV antiretroviral exposure in pregnancy induces detrimental placenta vascular changes that are rescued by progesterone supplementation.

Adverse birth outcomes are common in HIV-positive pregnant women receiving combination antiretroviral therapy (cART), especially when cART is initiated in early pregnancy. The mechanisms remain poorly understood. Using a mouse model we demonstrate that protease inhibitor based-cART exposure beginning on day 1 of pregnancy was associated with a pro-angiogenic/pro-branching shift in the placenta driven by lower Flt-1 levels and higher Gcm-1 expression. Micro-CT imaging revealed an increase in the number of arterioles in cART-treated placentas, which correlated with fetal growth restriction. Delaying initiation of cART, or supplementing cART-treated mice with progesterone, prevented the pro-angiogenic/pro-branching shift and the associated placenta vascular changes. In agreement with our mouse findings, we observed an increase in the number of terminal-villi capillaries in placentas from HIV-positive cART-exposed women compared to HIV-negative controls. Capillary number was inversely correlated to maternal progesterone levels. Our study provides evidence that cART exposure during pregnancy influences placenta vascular formation that may in turn contribute to fetal growth restriction. Our findings highlight the need for closer investigation of the placenta in HIV-positive pregnancies, particularly for pregnancies exposed to cART from conception, and suggest that progesterone supplementation could be investigated as a possible intervention to improve placenta function in HIV-positive pregnant women.

High Glucose Level Disturbs the Resveratrol-Evoked Curtailment of CX3CL1/CX3CR1 Signaling in Human Placental Circulation.

Hyperglycemia-induced hyperactivity of chemokine CX3CL1 (fractalkine) occurs in the human placenta. Anti-inflammatory/antioxidant activities of resveratrol (3,5,4'-trihydroxy-trans-stilbene) are related to the modulation of chemokine CX3CL1 and its receptor, CX3CR1, signaling pathways. We examined the influence of high glucose (25 mmol/L glucose; HG group; N = 36) on resveratrol-mediated effects on CX3CL1 and TNF-α production by the placental lobule, CX3CR1 expression and contents of CX3CR1, TNF-α receptor 1 (TNFR1), and NF-κB proteins in placental tissue. The placental lobules perfused under normoglycemic conditions formed the control NG group (N = 36). Resveratrol (50 and 100 µM; subgroups B and C) administered into the perfusion fluid lowered the production of both CX3CL1 and TNF-α. The reductions in CX3CL1 levels were more evident in the NG group. CX3CR1 expression was significantly higher in the NG subgroups B and C compared to the HG subgroups B and C (385.2 and 426.5% versus 199.3 and 282.4%, resp.). An increase in CX3CR1 protein content in placental lysates was observed in the NG subgroups B and C. Also, resveratrol significantly decreased NF-κBp65 protein content only in the NG group, not affecting hyperglycemia-elicited TNFR1 upregulation. In conclusion, euglycemia assures optimal effects of resveratrol pertaining to CX3CL1/CX3CR1 signaling in the placenta. Future studies on resveratrol are needed, especially those including maternal-fetal risk assessments.

Role of Tumor Necrosis Factor-α and Natural Killer Cells in Uterine Artery Function and Pregnancy Outcome in the Stroke-Prone Spontaneously Hypertensive Rat.

Women with chronic hypertension are at increased risk of maternal and fetal morbidity and mortality. We have previously characterized the stroke-prone spontaneously hypertensive rat (SHRSP) as a model of deficient uterine artery function and adverse pregnancy outcome compared with the control Wistar-Kyoto. The activation of the immune system plays a role in hypertension and adverse pregnancy outcome. Therefore, we investigated the role of tumor necrosis factor-α in the SHRSP phenotype in an intervention study using etanercept (0.8 mg/kg SC) at gestational days 0, 6, 12, and 18 in pregnant SHRSP compared with vehicle-treated controls (n=6). Etanercept treatment significantly lowered systolic blood pressure after gestational day 12 and increased litter size in SHRSP. At gestational day 18, etanercept improved the function of uterine arteries from pregnant SHRSP normalizing the contractile response and increasing endothelium-dependent relaxation, resulting in increased pregnancy-dependent diastolic blood flow in the uterine arteries. We identified that the source of excess tumor necrosis factor-α in the SHRSP was a pregnancy-dependent increase in peripheral and placental CD3- CD161+ natural killer cells. Etanercept treatment also had effects on placental CD161+ cells by reducing the expression of CD161 receptor, which was associated with a decrease in cytotoxic granzyme B expression. Etanercept treatment improves maternal blood pressure, pregnancy outcome, and uterine artery function in SHRSP by antagonizing signaling from excess tumor necrosis factor-α production and the reduction of granzyme B expression in CD161+ natural killer cells in SHRSP.

Vitamin C supplementation ameliorates the adverse effects of nicotine on placental hemodynamics and histology in nonhuman primates.

OBJECTIVE: We previously demonstrated that prenatal nicotine exposure decreases neonatal pulmonary function in nonhuman primates, and maternal vitamin C supplementation attenuates these deleterious effects. However, the effect of nicotine on placental perfusion and development is not fully understood. This study utilizes noninvasive imaging techniques and histological analysis in a nonhuman primate model to test the hypothesis that prenatal nicotine exposure adversely effects placental hemodynamics and development but is ameliorated by vitamin C. STUDY DESIGN: Time-mated macaques (n = 27) were divided into 4 treatment groups: control (n = 5), nicotine only (n = 4), vitamin C only (n = 9), and nicotine plus vitamin C (n = 9). Nicotine animals received 2 mg/kg per day of nicotine bitartrate (approximately 0.7 mg/kg per day free nicotine levels in pregnant human smokers) from days 26 to 160 (term, 168 days). Vitamin C groups received ascorbic acid at 50, 100, or 250 mg/kg per day with or without nicotine. All underwent placental dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) at 135-140 days and Doppler ultrasound at 155 days to measure uterine artery and umbilical vein velocimetry and diameter to calculate uterine artery volume blood flow and placental volume blood flow. Animals were delivered by cesarean delivery at 160 days. A novel DCE-MRI protocol was utilized to calculate placental perfusion from maternal spiral arteries. Placental tissue was processed for histopathology. RESULTS: Placental volume blood flow was significantly reduced in nicotine-only animals compared with controls and nicotine plus vitamin C groups (P = .03). Maternal placental blood flow was not different between experimental groups by DCE-MRI, ranging from 0.75 to 1.94 mL/mL per minute (P = .93). Placental histology showed increased numbers of villous cytotrophoblast cell islands (P < .05) and increased syncytiotrophoblast sprouting (P < .001) in nicotine-only animals, which was mitigated by vitamin C. CONCLUSION: Prenatal nicotine exposure significantly decreased fetal blood supply via reduced placental volume blood flow, which corresponded with placental histological findings previously associated with cigarette smoking. Vitamin C supplementation mitigated the harmful effects of prenatal nicotine exposure on placental hemodynamics and development, suggesting that its use may limit some of the adverse effects associated with smoking during pregnancy.

Effects of a single course versus repeated courses of antenatal corticosteroids on fetal growth, placental morphometry and the differential regulation of vascular endothelial growth factor.

AIM: To investigate the impact of antenatal exposure to a single course or repeated courses of dexamethasone (DEX) on neonatal anthropometrics, placental morphometry and potential effect on maternal plasma levels and placental expression of vascular endothelial growth factor (VEGF). METHODS: Pregnant women between 27 and 32 weeks of gestation who delivered between 28 and 40 weeks and received a single course (n = 38) or repeated courses (n = 33) of DEX were compared to gestational age-matched controls (n = 30). Maternal blood samples were obtained, and placental biopsy was taken. Area percent of VEGF immunostaining and villous capillarization index were evaluated using image analysis. RESULTS: Infants exposed to repeated courses of DEX were significantly associated with decreased birthweight, body length, head circumference and placental weight compared with controls (P = 0.011, P < 0.001, P = 0.004, P < 0.001, respectively) and with the group that received a single course of DEX (P = 0.021, P = 0.020, P = 0.049, P = 0.010, respectively). There was a significant decrease in maternal VEGF plasma levels and percentage of VEGF immunostained area after repeated courses of DEX compared with controls (P < 0.001 and P = 0.001, respectively) or a single course (P = 0.028 and P = 0.002, respectively). Notably, repeated courses of DEX impaired normal increase in villous capillarization index compared with controls or a single course (P = 0.001 and P = 0.041, respectively). CONCLUSION: Repeated antenatal courses of DEX compromised fetal and placental growth compared with a single course of DEX, and these effects were potentially mediated by altered maternal plasma levels and placental expression of VEGF with consequent decrease in placental vascularization. Because of continuing uncertainties, several key messages for clinicians are provided.

Assessment of sub-endometrial blood flow parameters following dydrogesterone and micronized vaginal progesterone administration in women with idiopathic recurrent miscarriage: a pilot study.

AIM: To evaluate differences in uteroplacental blood flow and pregnancy outcome in women with idiopathic recurrent spontaneous miscarriage (IRSM) following administration of micronized vaginal progesterone and oral dydrogesterone. METHODS: One hundred and thirty-three women (aged 23-40 years) who had had early miscarriages and spontaneous conception participated. Oral dydrogesterone (group A, n = 51) and micronized vaginal progesterone (group B, n = 50) were administrated for luteal support and compared. Pregnant women without history of recurrent miscarriage served as controls (group C, n = 32). The outcome measures consisted of endometrial blood flow parameters by Doppler indices and ongoing pregnancy rate. RESULTS: Before progesterone supplementation, resistivity index (RI) and pulsatility index (PI) were found to be significantly higher in groups A and B as compared to controls. Although statistically not significant, end diastolic velocity (EDV) and systolic/diastolic (S/D) ratio was found to be superior in controls than IRSM women. Peak systolic velocity (PSV) was comparable between IRSM and non-IRSM groups. Following progesterone supplementation, groups A and B showed a highly significant reduction in RI, PI and an increase in EDV. A relative increase in the value of PSV was observed in group A as compared to group B. There was remarkable difference in S/D in both groups. Although not statistically significant, group C showed reduction in RI, PI, PSV, EDV and S/D ratio. Pregnancy salvage rates were higher in group A (92.0%) as compared to group B (82.3%). CONCLUSION: Progesterone supplementation appears to lower vascular resistance in women with IRSM. Oral dydrogesterone appears to be equally effective in improving endometrial blood flow as compared with micronized progesterone.

Chronic binge alcohol exposure during pregnancy impairs rat maternal uterine vascular function.

BACKGROUND: Alcohol exposure during pregnancy results in an array of structural and functional abnormalities called fetal alcohol spectrum disorders (FASD). Alcohol dysregulates the exquisite coordination and regulation of gestational adaptations at the level of the uterine vasculature. We herein hypothesized that chronic binge-like alcohol results in uterine vascular dysfunction and impairs maternal uterine artery reactivity to vasoconstrictors and dilators. METHODS: We utilized a once-daily binge alcohol (4.5 g/kg body weight) exposure paradigm (gestational day 7 to 17) in a pregnant rat model system and investigated primary uterine artery function in response to vasoconstrictors and vasodilators utilizing wire myography. RESULTS: Alcohol (peak blood alcohol concentration, 216 mg/dl) produced uterine vascular dysfunction. Alcohol did not produce altered uterine vascular reactivity to α1 adrenergic agonist phenylephrine or the prostanoid thromboxane. However, alcohol specifically impaired acetylcholine (ACh)-mediated uterine artery vasodilation but exogenous endothelium-independent vasodilators like sodium nitroprusside exhibited no alcohol effect; ACh significantly decreased vessel relaxation (p = 0.003; ↓pD2 [negative log molar ACh concentration producing the half maximum response], -7.004 ± 0.215 vs. -6.310 ± 0.208; EMax [maximal ACh response], 92% vs. 75%). CONCLUSIONS: We conclude that moderate alcohol exposure impairs uterine vascular function in pregnant mothers. Alcohol specifically impairs agonist-induced uterine artery vasodilation. In summary, the maternal uterine compartment may play a significant role in the pathogenesis of FASD. Thus, the mechanistic targets of alcohol at the level of both the mother and the fetus need to be considered in order to develop effective therapeutic treatment strategies for FASD.

Maternal omega-3 fatty acid intake increases placental labyrinthine antioxidant capacity but does not protect against fetal growth restriction induced by placental ischaemia-reperfusion injury.

Placental oxidative stress plays a key role in the pathophysiology of several placenta-related disorders. Oxidative stress occurs when excess reactive oxygen species (ROS) damages cellular components, an outcome limited by antioxidant enzymes; mitochondrial uncoupling protein 2 (UCP2) also limits ROS production. We recently reported that maternal dietary omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation reduced placental oxidative damage and enhanced fetal and placental growth in the rats. Here, we examined the effect of n-3 PUFAs on placental antioxidant defences and whether n-3 PUFA supplementation could prevent growth restriction induced by placental ischaemia-reperfusion (IR), a known inducer of oxidative stress. Rats were fed either standard or high-n-3 PUFA diets from day 1 of pregnancy. Placentas were collected on days 17 and 22 in untreated pregnancies (term=day 23) and at day 22 following IR treatment on day 17. Expression of several antioxidant enzyme genes (Sod1, Sod2, Sod3, Cat, Txn1 and Gpx3) and Ucp2 was measured by quantitative RT-PCR in the placental labyrinth zone (LZ) and junctional zone (JZ). Cytosolic superoxide dismutase (SOD), mitochondrial SOD and catalase (CAT) activities were also analyzed. Maternal n-3 PUFA supplementation increased LZ mRNA expression of Cat at both gestational days (2- and 1.5-fold respectively; P<0.01) and female Sod2 at day 22 (1.4-fold, P<0.01). Cytosolic SOD activity increased with n-3 PUFA supplementation at day 22 (1.3-fold, P<0.05). Sod1 and Txn1 expression decreased marginally (30 and 22%, P<0.05). JZ antioxidant defences were largely unaffected by diet. Despite increased LZ antioxidant defences, maternal n-3 PUFA supplementation did not protect against placental IR-induced growth restriction of the fetus and placental LZ.

Dietary melatonin supplementation alters uteroplacental amino acid flux during intrauterine growth restriction in ewes.

Dietary melatonin supplementation during mid- to late-gestation increased umbilical artery blood flow and caused disproportionate fetal growth. This melatonin-induced increase in umbilical artery blood flow may alter nutrient availability to the fetus, which may lead to alterations in fetal size. The objectives of the current experiment were to determine amino acid (AA) and glucose concentrations as well as AA and glucose flux across the uteroplacenta using a mid- to late-gestation model of intrauterine growth restriction supplemented with dietary melatonin as a 2 × 2 factorial design. At day 50 of gestation, 32 ewes were supplemented with 5 mg of melatonin (MEL) or no melatonin (CON) and were allocated to receive 100% (adequate; ADQ) or 60% (restricted; RES) of nutrient requirements. On day 130 of gestation, uterine and umbilical blood flows were determined via Doppler ultrasonography during a non-survival surgery. Blood samples were collected under general anesthesia from the maternal saphenous artery, gravid uterine vein, umbilical artery, and umbilical vein for AA analysis and glucose. Total α-AA concentrations in maternal artery and gravid uterine vein were decreased (P < 0.05) in RES v. ADQ fed ewes. Maternal arterial - venous difference in total α-AA was increased (P ⩽ 0.01) in RES v. ADQ fed ewes, while total uterine α-AA flux was not different (P > 0.40) across all treatment groups. Fetal venous - arterial difference in total α-AA as well as uteroplacental flux of total α-AA were decreased (P < 0.05) in CON-RES v. CON-ADQ, and similar (P > 0.20) in MEL-RES v. CON-ADQ. Maternal concentrations and uterine flux of branched-chain AA (BCAA) were not different across all treatment groups; however, fetal uptake of BCAA was decreased (P < 0.05) in CON-RES v. CON-ADQ, and similar (P > 0.20) in MEL-RES v. CON-ADQ. Uterine uptake of glucose was not different (P ⩾ 0.08) across all treatment groups, while uteroplacental uptake of glucose was increased (P ⩽ 0.05) in RES v. ADQ ewes. In conclusion, maternal nutrient restriction increased maternal arterial - venous difference in total α-AA, while total uterine α-AA flux was unaffected by maternal nutrient restriction. Melatonin supplementation did not impact maternal serum concentrations or uterine flux of glucose or AA; however, melatonin did improve fetal BCAA uptake during maternal nutrient restriction.

Sildenafil attenuates placental ischemia-induced hypertension.

Preeclampsia is a complication of pregnancy that is marked by hypertension, proteinuria, and maternal endothelial dysfunction. A central factor in the etiology of the disease is the development of placental hypoxia/ischemia, which releases pathogenic soluble factors. There is currently no effective treatment for preeclampsia, but the phosphodiesterase-5 (PDE-5) inhibitor sildenafil has been suggested, as PDE-5 is enriched in the uterus, and its antagonism could improve uteroplacental function. Here, we report in the reduced uterine perfusion pressure (RUPP) rat model that administration of oral sildenafil is effective in attenuating placental ischemia-induced hypertension during gestation. RUPP animals have significantly elevated arterial pressure compared with control animals (132 ± 3 vs. 100 ± 2 mmHg; P < 0.05). Administration of oral sildenafil (45 mg·kg⁻¹·day⁻¹) had no effect on blood pressure in control rats but decreased pressure in RUPP rats (115 ± 1 mmHg; P < 0.05). RUPP induced changes in placental sFlt-1, and vascular endothelial growth factor (VEGF) was unaffected by sildenafil administration, as was the decrease in free plasma VEGF. RUPP animals had a significant increase in medullary PDE-5/ß-actin ratio (1 ± 0.14 vs. 1.63 ± 0.18; P < 0.05) expression with a resulting reduction in renal medullary cGMP (1.5 ± 0.15 vs. 0.99 ± 0.1 pmol/µg protein, P < 0.05) compared with controls. Although sildenafil had no effect on renal medullary cGMP in control animals, it significantly increased cGMP in RUPP animals (1.3 ± 0.1 pmol/µg protein; P < 0.05). These data suggest that sildenafil might provide an effective therapeutic option for the management of hypertension during preeclampsia.

Decrease in inflammatory response does not prevent placental dysfunction after fetal cardiac bypass in goats.

OBJECTIVE: One of the most significant responses to fetal cardiac bypass is severe placental dysfunction characterized by increased vascular resistance. We tested the hypothesis that fetal cardiac bypass triggers the activation of nuclear factor kappa-B (NF-KB), a major regulator of inflammatory response, and that pharmacologic inhibition of NF-KB activation by pyrrolidine dithiocarbamate alleviates fetal cardiac bypass-induced placental dysfunction. METHODS: Fifteen pregnant goats at 120 to 140 days' gestation were equally divided into the control group with a sham procedure of fetal sternotomy and cannulation (CG), the fetal bypass group (FB), and the fetal bypass group with 300 mg pyrrolidine dithiocarbamate before sternotomy (FP). Fetal cardiac bypass was performed for 30 minutes. Umbilical arterial flow rate was measured by ultrasonic flowmeter and placental vascular resistance was calculated. Fetal plasma levels of nitric oxide (NO), endothlin-1 (ET-1), 6-keto-prostaglandin F1α (6-K), thromboxane B(2) (TXB2), interleukin 6 (IL-6), and tumor necrosis factor-α (TNF-α) were assayed. IL-6 and TNF-α mRNA were analyzed by real-time polymerase chain reaction. NF-KB activation was evaluated by electrophoretic mobility shift assay. RESULTS: Placental vascular resistance significantly increased in the FB and FP groups compared with the CG group. Increases in plasma levels of NO were observed in all 3 groups. Plasma levels of ET-1 rose significantly in the FB and FP groups without noticeable difference between them. Plasma levels of 6-K, TXB(2), IL-6, and TNF-α increased significantly in the FB group compared with the CG and FP groups. The transcription levels of IL-6 and TNF-α mRNA in the placental tissues of the FB group were significantly higher than in the FP and CG groups. The amount of activated NF-KB in the placental tissues of the FB group was also significantly higher than that in the FP and CG groups. CONCLUSIONS: Fetal cardiac bypass-induced inflammatory response possibly mediated by NF-KB caused placental dysfunction. Pharmacologic inhibition of NF-KB activation and decrease in the inflammatory response did not alleviate the placental dysfunction.

Impact of passive smoking on uterine, umbilical, and fetal middle cerebral artery blood flows.

PURPOSE: The aim of this study was to evaluate the influence of passive maternal smoking on blood flow velocities in arteries of the fetal-placental-maternal circulation. MATERIALS AND METHODS: A total of 79 pregnant women in their third trimester, including 33 passive smokers, 23 active smokers, and 23 nonsmoking controls, were enrolled in the study. Fetal biophysical indices were evaluated with B-mode scanning, whereas blood flow waveforms of uterine, umbilical, and fetal middle cerebral (MCA) arteries were analyzed with Doppler ultrasonography. RESULTS: There were significant differences among active smokers vs. passive smokers vs. controls with regard to the presence of a uterine artery diastolic notch (39.1% vs. 18.2% vs. 4.3%; P = 0.012); ratio of peak systolic/end-diastolic velocity of fetal MCA [3.73 ± 1.27 vs. 4.26 ± 1.20 vs. 5.00 ± 2.15, analysis of variance (ANOVA) P = 0.026]; resistance index of fetal MCA (0.74 ± 0.08 vs. 0.75 ± 0.07 vs. 0.80 ± 0.09; ANOVA P = 0.014); ratio of fetal MCA/umbilical artery resistance index (1.27 ± 0.20 vs. 1.24 ± 0.14 vs. 1.39 ± 0.21; ANOVA P = 0.011); and ratio of fetal MCA/umbilical artery pulsatility index (1.56 ± 0.44 vs. 1.63 ± 0.43 vs. 1.97 ± 0.54; ANOVA P = 0.046). CONCLUSION: Effects of passive maternal smoking on the fetal-placental-maternal unit were comparable to those with active maternal smoking as determined by the means of increased resistance in the maternal vasculature and adaptive changes of cerebroplacental circulation for maintaining fetal cerebral circulation.