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We previously demonstrated decreased placental perfusion, reduced amniotic fluid protein content, and increased pregnancy loss in a nonhuman primate model of gestational protein restriction. Here, our objective was to link these detrimental findings with a functional placental assessment. As blood flow is critical to maternal-fetal exchange, we hypothesized that a protein-restricted diet would impair placental taurine uptake. Pregnant rhesus macaques were maintained on either control chow (CON, n = 5), a 33% protein-restricted diet (PR33, n = 5), or a 50% PR diet (PR50, n = 5) prior to and throughout pregnancy. Animals were delivered on gestational day 135 (G135; term is G168). Taurine activity was determined in fresh placental villous explants. Taurine transporter (TauT) protein expression, placental growth factor (PLGF), and insulin-like growth factor (IGF)-1 and IGF-2 protein concentrations were measured, and histological assessment was performed. Fetal body weights and placental weights were comparable between all three groups at G135. Placental taurine uptake was decreased in PR33- and PR50-fed animals compared to CON, yet TauT expression was unchanged across groups. PLGF was significantly increased in PR50 vs. CON, with no change in IGF-1 or IGF-2 expression in placental homogenate from PR-fed animals. Accelerated villous maturation was observed in all PR50 cases, three of five PR33, and was absent in CON. We demonstrate conserved fetal growth, despite a decrease in placental taurine uptake. Increased expression of PLGF and expansion of the syncytiotrophoblast surface area in the severely protein-restricted animals suggest a compensatory mechanism by the placenta to maintain fetal growth.

Objective: To determine the dose-dependent effect of contemporary marijuana exposure on female menstrual cyclicity and reproductive endocrine physiology in a nonhuman primate model., Design: Research animal study., Setting: Research institute environment., Animals: Adult female rhesus macaques (6-12 years of age; n = 8)., Interventions: Daily delta-9-tetrahydrocannabinol (THC) edible at medically and recreationally relevant contemporary doses., Main Outcome Measures: Menstrual cycle length (MCL), anti-Müllerian hormone, prolactin, basal follicle-stimulating hormone (FSH), estradiol (E2) and progesterone, luteinizing hormone (LH), and thyroid-stimulating hormone., Results: The average before THC weight was 6.9 kg (standard deviation, 0.8), and at the highest THC dosing, the average weight was 7.2 kg (standard deviation, 0.8). With increasing THC dosing, MCL and FSH concentrations increased, while basal E2 concentration was stable. The average MCL concentration increased 4.0 days for each mg/7 kg/day of THC (95% CI, 1.4-6.6 days). Follicle-stimulating hormone concentration increased significantly with increasing THC dose, 0.34 ng/mL for each mg/7 kg/day of THC (95% CI, 0.14-0.57 ng/mL). No significant trends were observed between THC dosing and average basal progesterone, anti-Müllerian hormone, prolactin, LH, or thyroid-stimulating hormone concentrations., Conclusions: In rhesus macaques, a dose response toward increased MCL and basal FSH concentrations but plateau of basal E2 and LH concentrations was observed with increasing THC dosing, suggesting ovulatory dysfunction. Further studies are needed to determine the effects of a longer duration of exposure and whether the significant increase in MCL and FSH concentrations results in reduced fecundity.

Background: Ureaplasma parvum infection is a prevalent cause of intrauterine infection associated with preterm birth, preterm premature rupture of membranes, fetal inflammatory response syndrome, and adverse postnatal sequelae. Elucidation of diagnostic and treatment strategies for infection-associated preterm labor may improve perinatal and long-term outcomes for these cases., Objective: This study assessed the effect of intraamniotic Ureaplasma infection on fetal hemodynamic and cardiac function and the effect of maternal antibiotic treatment on these outcomes., Study Design: Chronically catheterized pregnant rhesus monkeys were assigned to control (n=6), intraamniotic inoculation with Ureaplasma parvum (10 7 colony-forming units/mL, n=15), and intraamniotic infection plus azithromycin treatment (12.5 mg/kg twice a day intravenously, n=8) groups. At approximately 135 days' gestation (term=165 days), pulsed and color Doppler ultrasonography was used to obtain measurements of fetal hemodynamics (pulsatility index of umbilical artery, ductus venosus, descending aorta, ductus arteriosus, aortic isthmus, right pulmonary artery, middle cerebral artery and cerebroplacental ratio, and left and right ventricular cardiac outputs) and cardiac function (ratio of peak early vs late transmitral flow velocity [marker of ventricular function], Tei index [myocardial performance index]). These indices were stratified by amniotic fluid proinflammatory mediator levels and cardiac histology., Results: Umbilical and fetal pulmonary artery vascular impedances were significantly increased in animals from the intraamniotic inoculation with Ureaplasma parvum group (P<.05). Azithromycin treatment restored values to control levels. Amniotic fluid prostaglandin F2 alpha levels were significantly higher in animals with abnormal umbilical artery pulsatility index (>1.1) than in those with normal blood flow (P<.05; Spearman ρ=0.6, P<.05). In the intraamniotic inoculation with Ureaplasma parvum group, left ventricular cardiac output was significantly decreased (P<.001), and more animals had abnormal right-to-left ventricular cardiac output ratios (defined as >1.6, P<.05). Amniotic fluid interleukin-6 concentrations were elevated in cases of abnormal right-to-left ventricular cardiac output ratios compared with those in normal cases (P<.05)., Conclusion: Fetal hemodynamic alterations were associated with intraamniotic Ureaplasma infection and ameliorated after maternal antibiotic treatment. Doppler ultrasonographic measurements merit continuing investigation as a diagnostic method to identify fetal cardiovascular and hemodynamic compromise associated with intrauterine infection or inflammation and in the evaluation of therapeutic interventions or clinical management of preterm labor., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Although blood-brain barrier integrity is intact under normal pregnancy conditions, animal studies suggest that blood-brain barrier impairment occurs in preeclampsia. Yet, human data are limited, and the integrity of the blood-brain barrier has not been assessed in women with preeclampsia., Objective: We sought to test the hypothesis that the integrity of the blood-brain barrier is impaired and that neuroinflammation is increased in women with preeclampsia., Study Design: We performed an observational case-control study in pregnant women >24 weeks gestation who underwent spinal anesthesia for elective cesarean delivery or combined spinal epidural analgesia for labor. Cases were women with preeclampsia, and control subjects were women with either healthy pregnancy, chronic hypertension, or gestational hypertension. Paired samples of blood, urine, and cerebrospinal fluid were collected from each subject before delivery. We measured albumin, C5a, C5b-9, tumor necrosis factor-α, and interleukin-6 concentrations in plasma and cerebrospinal fluid, and albumin, C5a, and C5b-9 concentrations in urine, using colorimetric or enzyme-linked immunosorbent assays. The ratio of albumin in cerebrospinal fluid to plasma (Q alb ) was used as a surrogate for maternal blood-brain barrier integrity. Cerebrospinal fluid concentrations of C5a, C5b-9, tumor necrosis factor-α, and interleukin-6 were used as surrogate markers of neuroinflammation. Differences in Q alb and cerebrospinal fluid protein concentrations between groups were assessed by nonparametric test of medians., Results: Forty-eight subjects were enrolled, which included 16 cases with preeclampsia, 16 control subjects with healthy pregnancy, and 16 control subjects with either chronic or gestational hypertension. Q alb values were not increased in preeclampsia cases compared with healthy or hypertensive control subjects (Q alb median, 3.5 [interquartile range, 2.9-5.1] vs 3.9 [interquartile range, 3.0-4.8] vs 3.9 [interquartile range, 3.0-4.8]; P=.78]. Moreover, Q alb values were not increased in the subset of women with preeclampsia with severe features (n=8) compared with those without severe features (n=8; Q alb median, 3.5 [interquartile range, 3.3-4.9] vs 3.7 [interquartile range, 2.3-5.5]; P=.62]. Cerebrospinal fluid concentrations of C5a, C5b-9, tumor necrosis factor-α and interleukin-6 were not increased in cases of preeclampsia, compared with control subjects with either healthy pregnancy, chronic hypertension, or gestational hypertension (P>.05, all comparisons). In contrast to the negative findings in cerebrospinal fluid, plasma concentrations of both C5b-9 and interleukin-6 and urine concentrations of C5a and C5b-9 were increased in cases of preeclampsia., Conclusion: Through measurements of albumin, complement proteins, and cytokines in paired samples of blood and cerebrospinal fluid at the time of delivery, we found no evidence of blood-brain barrier impairment or neuroinflammation in preeclampsia. Larger studies that will investigate a wider range of proteins are suggested to validate our findings., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Prenatal alcohol exposure leads to impaired fetal growth, brain development, and stillbirth. Placental impairment likely contributes to these adverse outcomes, but the mechanisms and specific vasoactive effects of alcohol that links altered placental function to impaired fetal development remain areas of active research., Objective: Recently, we developed magnetic resonance imaging techniques in nonhuman primates to characterize placental blood oxygenation through measurements of T 2 * and perfusion using dynamic contrast-enhanced magnetic resonance imaging. The objective of this study was to evaluate the effects of first-trimester alcohol exposure on macaque placental function and to characterize fetal brain development in vivo., Study Design: Timed-pregnant Rhesus macaques (n=12) were divided into 2 groups: control (n=6) and ethanol exposed (n=6). Animals were trained to self-administer orally either 1.5 g/kg/d of a 4% ethanol solution (equivalent to 6 drinks/d) or an isocaloric control fluid from preconception until gestational day 60 (term is G168). All animals underwent Doppler ultrasound scanning followed by magnetic resonance imaging that consisted of T 2 * and dynamic contrast-enhanced measurements. Doppler ultrasound scanning was used to measure uterine artery and umbilical vein velocimetry and diameter to calculate uterine artery volume blood flow and placental volume blood flow. After noninvasive imaging, animals underwent cesarean delivery for placenta collection and fetal necropsy at gestational day 110 (n=6) or 135 (n=6)., Results: Fetal weight and biparietal diameter were significantly smaller in ethanol-exposed animals compared with control animals at gestational day 110. By Doppler ultrasound scanning, placental volume blood flow was significantly lower (P=.04) at gestational day 110 in ethanol-exposed vs control animals. A significant reduction in placental blood flow was evident by dynamic contrast-enhanced magnetic resonance imaging. As we demonstrated recently, T 2 * values vary throughout the placenta and reveal gradients in blood deoxyhemoglobin concentration that range from highly oxygenated blood (long T 2 *) proximal to spiral arteries to highly deoxygenated blood (short T 2 *). Distributions of T 2 *throughout the placenta show significant global reduction in T 2 * (and hence high blood deoxyhemoglobin concentration) in ethanol-exposed vs control animals at gestational day 110 (P=.02). Fetal brain measurements indicated impaired growth and development at gestational day 110, but less so at gestational day 135 in ethanol-exposed vs control animals., Conclusion: Chronic first-trimester ethanol exposure significantly reduces placental perfusion and oxygen supply to the fetal vasculature later in pregnancy. These perturbations of placental function are associated with fetal growth impairments. However, differences between ethanol-exposed and control animals in placental function and fetal developmental outcomes were smaller at gestational day 135 than at gestational day 110. These findings are consistent with placental adaptation to early perturbations that allow for compensated placental function and maintenance of fetal growth., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: The uteroplacental vascular supply is a critical determinant of placental function and fetal growth. Current methods for the in vivo assessment of placental blood flow are limited., Objective: We demonstrate the feasibility of the use of contrast-enhanced ultrasound imaging to visualize and quantify perfusion kinetics in the intervillous space of the primate placenta., Study Design: Pregnant Japanese macaques were studied at mid second trimester and in the early third trimester. Markers of injury were assessed in placenta samples from animals with or without contrast-enhanced ultrasound exposure (n = 6/group). Human subjects were recruited immediately before scheduled first-trimester pregnancy termination. All studies were performed with maternal intravenous infusion of lipid-shelled octofluoropropane microbubbles with image acquisition with a multipulse contrast-specific algorithm with destruction-replenishment analysis of signal intensity for assessment of perfusion., Results: In macaques, the rate of perfusion in the intervillous space was increased with advancing gestation. No evidence of microvascular hemorrhage or acute inflammation was found in placental villous tissue and expression levels of caspase-3, nitrotyrosine and heat shock protein 70 as markers of apoptosis, nitrative, and oxidative stress, respectively, were unchanged by contrast-enhanced ultrasound exposure. In humans, placental perfusion was visualized at 11 weeks gestation, and preliminary data reveal regional differences in intervillous space perfusion within an individual placenta. By electron microscopy, we demonstrate no evidence of ultrastructure damage to the microvilli on the syncytiotrophoblast after first-trimester ultrasound studies., Conclusions: Use of contrast-enhanced ultrasound did not result in placental structural damage and was able to identify intervillous space perfusion rate differences within a placenta. Contrast-enhanced ultrasound imaging may offer a safe clinical tool for the identification of pregnancies that are at risk for vascular insufficiency; early recognition may facilitate intervention and improved pregnancy outcomes., (Copyright © 2016 Elsevier Inc. All rights reserved.)

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., (Copyright © 2015 Elsevier Inc. All rights reserved.)

The aim of this study was to use proteomic approaches to examine differences in protein expression in placentae from normal term and preterm preeclamptic pregnancies and to validate the data thus obtained by other independent methods. Using 2-DE we found that 80% of the proteins were present in both normal and preeclamptic placentae. However, 26 proteins in the normal term placentae were not matched in the preterm preeclamptic group. Six proteins showed increased intensity and one protein was down-regulated in preeclampsia. Four of the seven proteins that were altered in preeclampsia were further analyzed by Western blot and immunohistochemistry. Identification by MS techniques revealed these proteins to be involved in regulatory pathways activated by stress. This is significant because preeclampsia is a multisystem disorder in human pregnancies that results in considerable oxidative and nitrative stress. Three proteins identified by MS to be Hsp27, catalase, and glucose-regulated protein were confirmed by Western blot analysis to be significantly up-regulated in preeclampsia. Endothelial monocyte-activating polypeptide was shown to be down-regulated in preeclampsia by 2-DE and MS., (Copyright © 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)