Placental Vascularization Research Articles

The profile of villous chorion vascularization in primary placental insufficiency

Introduction. Placentation and autochthonous vascularization during the early period of intrauterine development in primary placental insufficiency are important stages in the establishment of embryo-haemochorial circulation. Vascular and angiogenesis dysfunctions in the early period of gestation are essential in the development of changes in placental vascular status with severe repercussions on pregnancy outcome in the first trimester of gestation. The purpose of the work. Evaluation of vascular density by the application of the anti-CD31 antibody in the chorio-villar germinal site in short-term dysregulated pregnancies. Material and methods. 184 cases were divided into 2 groups: stagnant pregnancies (SP (L1 = 144 cases) and early spontaneous abortion (ESA) (L2 = 40 cases). Control material: pregnancies resolved at social indications/desire (A) (n = 18) distributed according to gestational term (3-5 weeks), (6-9 weeks), and (10-12weeks). The estimation of the histomorphological features was performed by applying the classical conventional method with hematoxylin-eosin (H.E.), and the immunohistochemical evaluation of the vascular density in the chorio-villar profile with the help of the endothelial marker anti-CD31. The statistical relationships between fetal conceptus assessment forms, gestational term, and age were analyzed. Results. Distribution of pregnancies by profile: (SP) – 78.2% vs (ESA) – 21.8%, with vascular disturbances attested in 100% of cases by increasing the density of avascular chorionic villi in the case of stagnant pregnancies in 75% of cases. The application of immunoexpression with anti-CD31 at the level of the stroma of the chorionic villi determined PVI with a maximum mean in the control group (91.51±0.71) vs the ESA and SP groups (82.29±12.96 and 57.47±6.53, respectively). The index of vascularization with lumen (IV/L+) and vascularization index without lumen (IV/L-) were statistically significantly different (p = 0.011) for (SP). Applying the student t-test revealed statistically significant differences for PVI in most groups, except PSD vs SP at the age of 10-12 gestation of weeks (w.g.) At the same time, there are statistically significant differences between the means of vessels with lumen within PSD and SP (t31 = 5.500, p = 0.000005), and the means of vessels without lumen registered statistically significant differences in the PSD and SP groups (t12 = 3.862, p = 0.002). Conclusions. Pregnancy evolution depends on the degree of vascularization, as well as on the quality of the vascular network.

Ang2 immunoexpression vs vascular profile in chorio-villous germinative status in early term compromised pregnancies

Background: The angiopoietin/TIE system is one of the signalling pathways that regulate vascular development and remodelling during morphogenesis of the placental complex. Deregulation of the vascularization process is associated with primary placental insufficiency through destabilization of the maternal-fetal functional system. Disruption of expression of pro-angiogenic factors is associated with reduction of the microcirculatory bed and installation of circulatory dysfunction. The aim: Evaluation of Ang2 immunoexpression in early term compromised uterine pregnancies in the context of chorio-villous circulatory dysfunction in primary placental insufficiency. Material and methods: Abortion product from 67 patients with early term compromised pregnancies (stagnant pregnancies – 43 cases, early miscarriages – 11 cases, control batch that included 13 cases of pregnancies solved on social indications) were immunohistochemically evaluated with the marker for anti-Ang2 and anti-CD31. Results: The majority of sites analyzed were Ang2 negative, with the exception of syncytiotrophoblast, that reached the highest score (+3) in most cases. A maximum placental vascularisation index was achieved in the control group. The stagnant pregnacies batch has registered the lowest vascular density mean. Conclusions: The placentation period is characterized by a weak Ang2 cellular environment in the chorio-villous germinal site in the group of short-term compromised pregnancies, except a highly positive syncytiotrophoblast. The immunoexpression profile in vascular endothelium correlates statistically significantly with placental vascularization index and chorio-villous vascular density in stagnant pregnancies.

In Vivo Quantitative Assessment of Gestational Choriocarcinoma Development and Progression Using Luminescent Trophoblast Cells.

Gestational trophoblastic diseases (GTD) are a group of pregnancy-related disorders representing rare human tumors. Among GTD is the gestational choriocarcinoma (CC), which is a highly malignant gestational trophoblastic tumor that causes high mortality without timely treatment. The incidence of CC is about 1 in 50,000 pregnancies in developed countries and even higher in developing countries. CC developed from molar pregnancies exhibits even higher incidence rates (3-20 in 1000 pregnancies). In the present invention, we developed the first orthotopic animal model of CC. We demonstrate how to mimic the development of this cancer and observe rapid metastasis, which is seen in CC patients, by injecting the luciferase-positive JEG-3 (JEG-3-Luc) cells directly in the placenta of gravid SCID mice. Gravid mice were injected at 7.5days post coitus (dpc) and followed throughout gestation to assess the parameters of CC development and metastasis. Mice imaged at day 19.5dpc showed placental tumor development and large sites of metastases in the liver, spleen, lung, and peritoneum. This finding emphasizes the importance of placental vascularization in the rapid dissemination of tumor cells. Morphological analyses and histopathological examinations were performed to confirm JEG-3 cell dissemination in different organs of the gravid mice. This is the first time a CC model was developed by injection of tumor cells within the placenta. This technique offers a new tool to study tumor progression with strong perspectives to test anti-tumor agents in vivo.

Characterizing Pregnancy Outcomes in a Humanized Mouse Model of Sickle Cell Disease

Background: Sickle cell disease (SCD) is a group of hereditary disorders commonly associated with the distortion of red blood cells (RBC) at low oxygen levels. It is characterized by complications such as vaso-occlusion, anemia, and hemolysis. These complications are lifelong and become extremely relevant during periods of increased physiological stress such as pregnancy. Pregnancy in sickle cell disease (SCD) is associated with an increased risk of complications including, pre-term delivery, deep vein thrombosis, intra-uterine growth restriction, pre-eclampsia, and intra-uterine death. Recent meta-analyses have shown that women with SCD are at 26x greater risk for maternal mortality than their healthy counterparts; a figure which, despite the adoption of improved care plans, has shown little to no significant improvement over the last two decades. While impaired vascular maintenance underlies multiple complications of pregnancy outside of sickle cell disease, it is especially relevant to, and characteristic of sickle cell-related pathologies at baseline and is highly likely to be exacerbated as pregnancy proceeds. Through this study we aimed to characterize the effects of SCD-related vasculopathy on pregnancy outcomes and overall placental health using the Townes humanized mouse model of SCD. Methods: SS (sickle hemoglobin) and AA (normal hemoglobin) mice underwent timed breeding to produce pregnant dams. These dams were housed under normal conditions until 17.5 days post conception (dpc), at which point they began undergoing procedures for analysis including 24-hour urine collection, high-resolution ultrasound analysis (18.5dpc), and post-mortem analysis of pregnancy outcomes and tissue collection (18.5dpc). Included in this report are gross pregnancy outcomes, histological assessments of placental tissue, and reports from ultrasound analysis including 3-D volume measures, placental vascularization renders, and laser-Doppler assessment of uterine and umbilical arteries. Continuing research efforts will further utilize tissues from this study to evaluate the biochemical interactions influencing poor pregnancy outcomes related to SCD. Results: These studies show that the SCD mice recapitulate many similarly poor outcomes as women. We observed: reduced litter sizes (AA 6.9 ± 1.5 embryos vs SS 5.2 ± 1.2 embryos**), fetal weight (AA 0.49 ± 0.14g vs SS 0.38 ± 0.16g*), viability of embryos (AA 100.0% IQR 0.0 vs SS 20.0% IQR 33.3****), and maternal mortality (AA 0.0% vs SS 8.7%, OR = 4.3 ns). In assessing placental histology, we identified evidence of vasculopathy common to end organ damage in SCD such as increased presence of avascular areas, reduced relative labyrinth area (AA 55.6 ± 8.6% vs SS 44.7 ± 6.0%*) and reduced vascular density (AA 38.9 ± 6.2% vs SS 34.4 ± 7.0%*) which are likely responsible for worsening outcomes. Additional pathologies include increased occurrence of placental ectasia, calcification of the labyrinth, vascular thrombi, and perivascular fibrosis when compared to controls. Further, ultrasound analysis revealed several measures of placental insufficiency amongst SS mice that were significantly impaired including uterine blood flow and an overall reduction in placental vascularization and oxygenation. Conclusions: SCD mice demonstrate many similar pregnancy outcomes as humans, allowing for increased translational application. We've shown these outcomes to be severe and largely driven by vascular impairment specifically within the placenta, the main maternal-fetal interface. This study serves as the groundwork for future studies aimed at investigating the underlying mechanisms of these outcomes while also establishing baseline measures and novel methods of approach towards the broader goal of improving obstetric disparities faced by women with SCD.

PSVI-1 Elucidating the Effects of the CXCL12/CXCR4 Axis Through Hematological Changes in Sheep During Gestation

Abstract The placenta, an organ that develops during pregnancy, is essential for transporting nutrients and oxygen to the developing offspring. Formation of the placenta is characterized by many physiological and hematological changes necessary for a healthy gestation. Improper placentation causes placental insufficiency which increases fetal mortality and poor postnatal health and performance. Causes of placental insufficiency are poorly understood, however evidence indicates immune factors including the chemokine ligand 12 (CXCL12) and its receptor (CXCR4) regulate several processes central to placentation and white blood cells (WBC) have essential roles by promoting trophoblast invasion and supporting artery remodeling. We previously demonstrated suppressing CXCL12/CXCR4 signaling at the fetal-maternal interface during implantation diminishes placental vascularization, reduces trophoblast invasion, and creates an excessively inflammatory placental environment. Building on these studies, we hypothesized the negative impacts early in gestation would result in compromised placental development and altered hematological parameters during gestation. Identifying key hematological changes or inflammatory markers in a complete blood count analysis during pregnancy might provide diagnostic clues to placental insufficiency at early stages of pregnancy. Our objective was to determine if disrupting the CXCL12/CXCR4 axis during implantation results in an altered hematological profile or serum progesterone (P4) concentrations. Using an in-vivo sheep model osmotic pumps were surgically installed to deliver treatments into the uterine lumen on day 12 of gestation. Pumps delivered either CXCR4 inhibitor (AMD3100) at (1X, 1.5X, or 3X dose), CXCL12 at (low or high dose), or PBS (control) into the uterus over the course of 14 days. Blood samples were collected via jugular venipuncture daily from days 11 to 16 of gestation, every two days from days 18 to 30, and weekly from day 35 to 135 and analyzed within 2 h of collection for a complete blood count using the Abaxis VetScan HM5. Serum was also collected and P4 concentrations were quantified by radioimmunoassay. Manipulating the CXCL12/CXCR4 axis during early gestation did not affect (P = 0.98) systemic circulating progesterone values during days tested, but neutrophils, lymphocytes, WBCs, and platelets increased indicated systemic inflammation. Of the hematological parameters tested, WBC counts were increased (P < 0.05) in the 3X AMD3100 treatment group and neutrophils and lymphocytes tended (P < 0.1) to increase compared with control. Our results reveal that suppressing CXCL12/CXCR4 signaling during early gestation creates an inflammatory response reflected in circulation. A greater understanding of hematological changes and endometrial interactions involved in placentation in sheep is necessary to elucidate the causes of placental insufficiency and recurrent pregnancy loss. Future research will investigate if circulating markers indicative of placental dysfunction exist which may lead to methods to improve fertility, pregnancy outcomes, and fetal health.

The maternal microbiome promotes placental development in mice.

The maternal microbiome is an important regulator of gestational health, but how it affects the placenta as the interface between mother and fetus remains unexplored. Here, we show that the maternal gut microbiota supports placental development in mice. Depletion of the maternal gut microbiota restricts placental growth and impairs feto-placental vascularization. The maternal gut microbiota modulates metabolites in the maternal and fetal circulation. Short-chain fatty acids (SCFAs) stimulate cultured endothelial cell tube formation and prevent abnormalities in placental vascularization in microbiota-deficient mice. Furthermore, in a model of maternal malnutrition, gestational supplementation with SCFAs prevents placental growth restriction and vascular insufficiency. These findings highlight the importance of host-microbial symbioses during pregnancy and reveal that the maternal gut microbiome promotes placental growth and vascularization in mice.

EP18.33: Assessing placental vascularisation between 20 and 25 weeks using 3D vaginal power Doppler for the prediction of pre‐eclampsia: pilot study

EP18.33: Assessing placental vascularisation between 20 and 25 weeks using 3D vaginal power Doppler for the prediction of pre‐eclampsia: pilot study

Placental insufficiency and heavier placentas in sheep after suppressing CXCL12/CXCR4 signaling during implantation†.

During implantation, trophoblast cell invasion and differentiation is predominantly important to achieving proper placental formation and embryonic development. The chemokine, C-X-C motif chemokine ligand 12 (CXCL12) working through its receptor C-X-C motif chemokine receptor 4 (CXCR4) is implicated in implantation and placentation but precise roles of this axis are unclear. Suppressing CXCL12/CXCR4 signaling at the fetal-maternal interface in sheep reduces trophoblast invasion, disrupts uterine remodeling, and diminishes placental vascularization. We hypothesize these negative impacts during implantation will manifest as compromised fetal and placental growth at midgestation. To test, on day 12 postbreeding, osmotic pumps were surgically installed in 30 ewes and delivered intrauterine CXCR4 inhibitor or saline for 7 or 14days. On day 90, fetal/maternal tissues were collected, measured, weighed, and maternal (caruncle) and fetal (cotyledon) placenta components separated and analyzed. The objectives were to determine if (i) suppressing CXCL12/CXCR4 during implantation results in reduced fetal and placental growth and development and (ii) if varying the amount of time CXCL12/CXCR4 is suppressed impacts fetal/placental development. Fetal weights were similar; however greater placental weight and placentome numbers occurred when CXCL12/CXCR4 was suppressed for 14days. In caruncles, greater abundance of fibroblast growth factor 2, vascular endothelial growth factor A, vascular endothelial growth factor A receptor 1 (FLT-1), and placental growth factor were observed after suppressing CXCL12/CXCR4. Similar results occurred in cotyledons except less vascular endothelial growth factor in 7day group and less fibroblast growth factor in 14day group. Our data underscore the importance of CXCL12/CXCR4 signaling during placentation and provide strong evidence that altering CXCL12-mediated signaling induces enduring placental effects manifesting later in gestation.

Maternal chronic caffeine intake impairs fertility, placental vascularization and fetal development in mice

Caffeine is commonly consumed by pregnant women to avoid fatigue or as a habit. However, it is not clearly determined its side effects to the conceptuses. This study evaluated placental morphofunctional alterations after maternal chronic caffeine intake and the effects on fetal growth. Female Swiss mice received, via gavage, caffeine doses (either 60, 120 or 240 mg/kg/day) seven days before mating until gestational days-(GD) 11.5 or 17.5. Fetal biometrical parameters were assessed, and placentae were either submitted to histomorphometrical or molecular evaluation of angiogenesis (placental growth factor-1[PlGF-1]), apoptosis (Caspase-3) and proliferation (Ki-67) markers (evaluated in Swiss dams) and to intravital microscopy (evaluated in C57BL/6 dams). Caffeine exposed fetuses exhibited intrauterine growth restriction in a sex-dependent manner, with greater commitment of female fetuses (P < 0.05). In addition, placentae from dams that received 120 mg/kg/day showed less irrigation by maternal blood and greater development of fetal vasculature, characterized by higher number of larger vessels (P < 0.05). Although no effects on apoptosis (Caspase-3) and angiogenesis (PlGF-1) were observed, dams treated with 60 mg/kg/day showed greater placental cell proliferation (Ki-67 staining) at GD 11.5 (P < 0.05). The group treated with 240 mg/kg/day exhibited only one pregnant dam for each gestational age, suggesting that this high caffeine consumption may compromise fertility. Taken together, even in the doses currently ingested by many pregnant women, caffeine has detrimental effects on placental vasculature and fetal development in mice. Therefore, our results strongly suggest that caffeine consumption in human pregnancies greater than the recommended doses should be avoided.

Role of Placental Vascularization Indices and Shear Wave Elastography in Fetal Growth Restriction.

To evaluate the role of placental vascularisation indices using 3D-Power Doppler and placental elasticity using Shear Wave Elastography (SWE) in Fetal Growth Restricted (FGR) pregnancies and to assess their correlation with perinatal outcomes. This prospective case-control study was conducted from June 2018-2020. Thirty women with FGR and thirty controls (24-36weeks) underwent grayscale and Doppler ultrasonography followed by measurement of vascularisation indices and SWE from the central and peripheral parts of fetal and maternal surfaces of the placenta. Participants were followed till delivery and perinatal outcomes were noted. Vascularisation indices were significantly reduced among FGR vs. controls: Vascularisation Index (VI): 20.90 ± 5.46 vs. 31.49 ± 3.89, Flow Index (FI): 26.29 ± 1.70 vs. 30.85 ± 2.02, Vascularisation- Flow Index (VFI): 7.06 ± 2.42 vs. 12.37 ± 2.43, p < 0.001. The mean placental SWE (17.36 ± 1.50kPa) in FGR pregnancies was significantly higher as compared to controls (4.14 ± 1.14kPa), p < 0.001. Neonatal polycythaemia and hyperbilirubinemia were significantly increased in FGR pregnancies with higher SWE value. Receiver operating characteristic curve-based cut-off of VI for intensive care requirement was 23.0 (sensitivity: 75%, specificity: 71%) and for tachypnea was 22.8 (73% sensitivity and specificity). The cut-off of FI for low birth weight was 25.7 (sensitivity: 69.6%, specificity: 71.4%). This study demonstrates that increased placental stiffness and reduced vascularisation in FGR indicate possible placental pathology. Both modalities help in predicting perinatal complications. Hence, vascularisation indices and SWE reflect the extent of placental insufficiency and can be useful adjuncts in diagnosis.

Malaria Infections and Placental Blood Flow: A Doppler Ultrasound Study From a Preconception Cohort in Benin.

Malaria in pregnancy (MiP) has been associated with fetal growth restriction, the underlying pathogenic mechanisms of which remain poorly understood. Malaria in pregnancy is suspected to induce abnormalities in placental vascularization, leading to impaired placental development. Our study evaluated MIP's effect on uterine artery (UtA) and umbilical artery (UA) blood flow. The analysis included 253 Beninese women followed throughout pregnancy and screened monthly for submicroscopic and microscopic malaria. Uterine artery Doppler measurement was performed once between 21 and 25 weeks' gestation (wg), and UA Doppler measurement was performed 1-3 times from 28 wg. Linear and logistic regression models were used to assess the effect of malaria infections on UtA Doppler indicators (pulsatility index and presence of a notch), whereas a logistic mixed model was used to assess the association between malaria infections and abnormal UA Doppler (defined as Z-score ≥2 standard deviation or absent/reversed UA end-diastolic flow). Primigravidae represented 7.5% of the study population; 42.3% of women had at least 1 microscopic infection during pregnancy, and 29.6% had at least 1 submicroscopic infection (and no microscopic infection). Both microscopic and submicroscopic infections before Doppler measurement were associated with the presence of a notch (adjusted odds ratio [aOR] 4.5, 95% confidence interval [CI] = 1.2-16.3 and aOR 3.3, 95% CI = .9-11.9, respectively). No associations were found between malaria before the Doppler measurement and abnormal UA Doppler. Malaria infections in the first half of pregnancy impair placental blood flow. This highlights the need to prevent malaria from the very beginning of pregnancy.

Common mechanisms of placental dysfunction in preeclampsia, gestational diabetes, and COVID-19 in pregnant women

COVID-19 infection, preeclampsia and gestational diabetes mellitus in pregnancy cause similar changes in the placenta and influence development of the fetus between conception and birth in gestation. Proper uterine and placental vascularization is essential for normal fetal development. The transplacental exchange is regulated and maintained by the placental endothelium. During placental implantation, the trophoblast differentiates into two distinct layers, the inner cytotrophoblast and outer syncytiotrophoblast, which are key elements of the human placental barrier. Proinflammatory cytokines exacerbate ischemic events and create an upward spiral of an inflammatory reaction in the placenta. Placental pathology in gestational COVID-19 shows desquamation and damage of trophoblast and chronic histiocytic intervillositis. Similar lesions also occur in gestational diabetes mellitus and preeclampsia. The systemic inflammatory response of the mother, the increased inflammation in the placenta and cytokine production by placental trophoblasts should be monitored throughout pregnancy. Placental angiogenesis can be evaluated by serum vascular endothelial growth factor, Annexin A2, placental growth factor or sclerostin. Tissue damage can be assessed by measuring levels of serum lactate dehydrogenase and myeloperoxidase. Blood flow can be monitored with three-dimensional Doppler and pathological changes can be documented with paraffin-embedded tissue sections stained with hematoxylin and eosin, and electron microscope images as well as immunohistochemistry tests for vascular endothelial growth factor, placental growth factor, sclerostin and Annexin A2. The damage of maternal and fetal vascular perfusion (villitis and fibrin deposition) is a common mechanism of gestational diseases. The placenta lesions liberate anti-endothelial factors that lead to anti-angiogenic conditions and are the common mechanism of maternal placental vascular malperfusion in gestational diseases. Keywords: dysfunction, inflammation, pathology, placenta, pregnancy, vascularization

Targeted Disruption of the MORG1 Gene in Mice Causes Embryonic Resorption in Early Phase of Development.

The mitogen-activated protein kinase organizer 1 (MORG1) is a scaffold molecule for the ERK signaling pathway, but also binds to prolyl-hydroxylase 3 and modulates HIFα expression. To obtain further insight into the role of MORG1, knockout-mice were generated by homologous recombination. While Morg1+/- mice developed normally without any apparent phenotype, there were no live-born Morg1-/- knockout offspring, indicating embryonic lethality. The intrauterine death of Morg1-/- embryos is caused by a severe failure to develop brain and other neuronal structures such as the spinal cord and a failure of chorioallantoic fusion. On E8.5, Morg1-/- embryos showed severe underdevelopment and proliferative arrest as indicated by absence of Ki67 expression, impaired placental vascularization and altered phenotype of trophoblast giant cells. On E9.5, the malformed Morg1-/- embryos showed defective turning into the final fetal position and widespread apoptosis in many structures. In the subsequent days, apoptosis and decomposition of embryonic tissue progressed, accompanied by a massive infiltration of inflammatory cells. Developmental aberrancies were accompanied by altered expression of HIF-1/2α and VEGF-A and caspase-3 activation in embryos and extraembryonic tissues. In conclusion, the results suggest a multifactorial process that causes embryonic death in homozygous Morg1 mutant mice, described here, to the best of our knowledge, for the first time.

Gestational Diabetes—Placental Expression of Human Equilibrative Nucleoside Transporter 1 (hENT1): Is Delayed Villous Maturation an Adaptive Pattern?

Gestational diabetes mellitus (GDM) is a metabolic disease that can affect placental villous maturation and villous vascularity. The main effects of GDM on placental growth are a delay of villous maturation (DVM) and decreased formation of vasculo-syncytial membranes (VSM). Human equilibrative nucleoside transporter-1 (hENT1) is an adenosine transporter expressed in the human umbilical vein endothelial cells (HUVEC) and human placental microvascular endothelium cells (hPMEC). Its role is crucial in maintaining physiological fetal adenosine levels during pregnancy, and its reduction has been described in GDM. Twenty-four placentas from pregnancies with a confirmed diagnosis of GDMd and twenty-four matched non-GDM placentas (controls) were retrospectively analyzed to investigate the immunohistochemical expression of hENT1 in HUVEC and hPMEC. The study included the quantitative evaluation of VSM/mm2 in placental tissue and the immunohistochemical quantitative evaluation of Ki-67, PHH3, and p57 in villous trophoblast. hENT1 expression was higher in all the vascular districts of the control cases compared to the GDMd placentas (p &lt; 0.0001). The VSM/mm2 were lower in the GDMd cases, while the Ki-67, PHH3, and p57 were higher when compared to the control cases. To our knowledge, this is the first report of hENT1 expression in the human placentas of GDM patients. The absence/low expression of hENT1 in all the GDMd patients may indicate a potential role in microvascular adaptative mechanisms. The trophoblasts’ proliferative/antiapoptotic pattern (high Ki-67, high PHH3, and high p57 count) may explain the statistically significant lower number of VSM/mm2 found in the GDMd cases.

The impact of in vitro embryo production on placental and umbilical cord vascularization is minimized by the addition of reproductive fluids

Animals born from in-vitro-produced (IVP) embryos show changes in the placenta and umbilical cord vascularization. This study compares the placental and umbilical vascular morphometry in pigs (n = 19) born through artificial insemination (AI group) or after transfer of IVP embryos cultured with (RF-IVP group) or without (C-IVP group) reproductive fluids. The relationship between vascular parameters and animal growth during the first year of life was also analyzed. Samples were collected at birth, fixed, paraffin-embedded, cut in sections, stained, and photographed for vascular and morphometric analysis with ImageJ® and Slide Viewer®. The average daily weight gain was individually scored from birth to the first year of life. No differences were found in placental vascular morphometry among groups, except for the vascular area of small vessels (arterioles, venules, and small vessels) that was higher in the C-IVP group. Regarding the umbilical cord, the values for perimeter (AI: 26.40 ± 3.93 mm; IVP: 30.51 ± 4.74 mm), diameter (AI: 8.35 ± 1.01 mm; IVP: 10.26 ± 1.85 mm), area (AI: 43.18 ± 12.87; IVP: 56.61 ± 14.89 mm2), and Wharton's jelly area (AI: 36.86 ± 12.04 mm2; IVP 48.88 ± 12.80 mm2) were higher in IVP-derived than AI-derived animals, whereas arterial and venous morphometric data were similar between groups. A correlation study showed that placental and umbilical cord vascular phenotypes affect the further growth of pigs. In conclusion, assisted reproductive technologies impact small caliber vessels in the placenta and morphometric parameters in the umbilical cord. The addition of reproductive fluids in IVP-embryo contributes to reduce the differences with in vivo-derived animals.

Mitochondrial-targeted antioxidant attenuates preeclampsia-like phenotypes induced by syncytiotrophoblast-specific Gq signaling

Generalized cellular ‘stress’ (i.e., oxidative, mitochondrial) within the syncytiotrophoblast (STB) layer of placenta is theorized to drive the pathogenesis of preeclampsia (PE), but the causes and consequences of this stress have yet to be clearly elucidated. Many hormones implicated in the disorder signal through the Gq pathway and have been associated with placental oxidative damage and maternal symptoms. Here, we provide novel evidence of elevated Gq stimulation (n=8-10 normalized area PLCB protein, control 1340±370, PE 3350±750, P=0.04) and an antioxidant response (n=8 normalized area SOD2 protein, control 3020±1160, PE 6700±1250, P=0.04) within STB cells of PE placenta. Thus, we hypothesized excess STB-specific Gq signaling would be sufficient to cause phenotypes of PE and that administration of a mitochondrial-targeted antioxidant (mitoquinone) would mitigate these effects. Activation of the Gq cascade in STB cells was achieved by crossing dams harboring a Cre-dependent Gq-coupled DREADD (hM3Dq) with Gcm1-Cre+/- sires and injecting clozapine N-oxide (CNO) or saline mid-gestation (GD12.5-14.5) before tissue collection at GD14.5. Gq stimulation increased mean arterial pressure (n=6-8, CNO 115±2mmHg, saline 110±2mmHg, GD 13-16.5, P=0.04), exacerbated urine protein excretion (n=9-11 CNO 43±4mg/d, saline 28±3mg/day, P=0.001), and elevated circulating pro-inflammatory factors (MCP5, LIX, TIMP1, MIP3B, GCSF, IL12p40, MDC, P&lt;0.05). Placental assessments revealed decreased labyrinth vascularization (n=10 CD31-positive area, Cre+ 19±1%, Cre– 24±1%, saline 23±1%, P&lt;0.01 Cre+ vs. each), diminished spiral artery diameter (n=7-12 Cre+ 113±10μm, saline 149±12μm, P=0.03), and augmented oxidant defenses to mitochondrial-derived superoxide (n=7-9 normalized area SOD2 protein, Cre+ 18.2±3, saline 4.5±0.4, P=0.003; RNA sequencing enrichment of genes related to superoxide metabolic process, FDR=0.09). Remarkably, administration of mitoquinone in CNO-injected pregnancies reduced urine protein excretion (22±4mg/day, P=0.005), decreased circulating pro-inflammatory factors (LIX, IL12p40, MDC, P&lt;0.05), attenuated plasma sFLT1 (P=0.048), and maintained placental vascularization (n=8 CD31-positive labyrinth, 23±1%, P=0.04; n=7 spiral artery diameter, 164±18 μm P=0.02). These data support a causative relationship between syncytiotrophoblast stress and the development of preeclampsia and identify elevated Gαq signaling as a contributing mechanism involving mitochondrial-derived reactive oxygen species. NIH: HL134850, HL084207, DK133121, HL150340; AHA: 826132, 18EIA33890055 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Alpha-2-macroglobulin is involved in the occurrence of early-onset pre-eclampsia via its negative impact on uterine spiral artery remodeling and placental angiogenesis

BackgroundPre-eclampsia (PE) is one of the leading causes of maternal and fetal morbidity/mortality during pregnancy, and alpha-2-macroglobulin (A2M) is associated with inflammatory signaling; however, the pathophysiological mechanism by which A2M is involved in PE development is not yet understood.MethodsHuman placenta samples, serum, and corresponding clinical data of the participants were collected to study the pathophysiologic mechanism underlying PE. Pregnant Sprague–Dawley rats were intravenously injected with an adenovirus vector carrying A2M via the tail vein on gestational day (GD) 8.5. Human umbilical artery smooth muscle cells (HUASMCs), human umbilical vein endothelial cells (HUVECs), and HTR-8/SVneo cells were transfected with A2M-expressing adenovirus vectors.ResultsIn this study, we demonstrated that A2M levels were significantly increased in PE patient serum, uterine spiral arteries, and feto-placental vasculature. The A2M-overexpression rat model closely mimicked the characteristics of PE (i.e., hypertension in mid-to-late gestation, histological and ultrastructural signs of renal damage, proteinuria, and fetal growth restriction). Compared to the normal group, A2M overexpression significantly enhanced uterine artery vascular resistance and impaired uterine spiral artery remodeling in both pregnant women with early-onset PE and in pregnant rats. We found that A2M overexpression was positively associated with HUASMC proliferation and negatively correlated with cell apoptosis. In addition, the results demonstrated that transforming growth factor beta 1 (TGFβ1) signaling regulated the effects of A2M on vascular muscle cell proliferation described above. Meanwhile, A2M overexpression regressed rat placental vascularization and reduced the expression of angiogenesis-related genes. In addition, A2M overexpression reduced HUVEC migration, filopodia number/length, and tube formation. Furthermore, HIF-1α expression was positively related to A2M, and the secretion of sFLT-1 and PIGF of placental origin was closely related to PE during pregnancy or A2M overexpression in rats.ConclusionsOur data showed that gestational A2M overexpression can be considered a contributing factor leading to PE, causing detective uterine spiral artery remodeling and aberrant placental vascularization.

Abstract P246: Association Between Life’s Essential 8 Cardiovascular Health Scores During Pregnancy and Vascular Integrity in the Placenta

Background: Adverse pregnancy outcomes (APOs) identify pregnant people at increased risk of later cardiovascular disease. Poor antenatal cardiovascular health (CVH) quantified using components of the Life’s Simple 7 ideal CVH framework has been associated with higher APO incidence, indicating modifiable aspects of CVH during pregnancy may be related to pregnancy health. Placental pathology is also common in APOs, but it is unclear if antenatal CVH is directly related to placental health. Further, clinically-used dichotomous measures of placental pathology limit investigation of associations. Thus, the aim of this study was to examine the relationship between antenatal CVH and a novel, continuous marker of placental vascularization. Hypothesis: We hypothesized higher (healthier) antenatal CVH scores would be associated with higher (healthier) vascularization in the placenta. Methods: Participants enrolled in the Magee Obstetric Maternal &amp; Infant Biobank and one of two prospective observational cohort studies examining activity patterns in pregnancy (MoM Health or Pregnancy 24/7). Antenatal CVH was quantified with a pregnancy-adapted Life’s Essential 8 framework assessed during each trimester and averaged across gestation. Components included sleep, diet, smoking, objective physical activity, pre-pregnancy BMI, blood pressure, 50g glucose challenge test results, and gestational weight gain. Component scores were averaged for a composite score (possible range, 0-100; higher indicated better CVH). Immunohistochemistry of placenta tissue was performed. Sections were stained with CD34 antibody to highlight vascular endothelial cells and counterstained with hematoxylin. Whole-slide images were digitized. Software computed the number of pixels positive for CD34 (numerator) and the total pixels (denominator); the ratio was the outcome of fetal vascular percentage (FV%), or the proportion of villous tissue occupied by fetal vessels. Linear regression associated CVH scores with FV%. Results: Placenta tissue was obtained from 64 participants (mean±SD age = 32±4.9 years). CVH score averaged across gestation was 72.6±10.7 points and decreased significantly from the first to third trimester (72.8±12.7 vs. 65.1±11.9, p&lt;0.01). FV% was 26.3±5.13 percentage points. Associations between CVH scores and FV% approached but did not reach significance (p&lt;0.2) in each trimester and across gestation. A 10-point increase in CVH averaged across gestation was non-significantly associated with a 0.82 percentage point increase in FV% (p=0.18). Post-hoc power analysis of this novel metric identified sufficient power to detect a 1.5 percentage point change in FV% per 10-point change in CVH score. Conclusion: Antenatal CVH was not significantly associated with placental vasculature, though a small sample size limits conclusions. Replication in a fully-powered sample is warranted.

Milyen az összefüggés a lepényi perfúzió vizsgálata során a teljes placenta vizsgálata és a szonobiopsziás módszer között?

Placental perfusion can be evaluated using three-dimensional power-Doppler (3DPD) indices with sonobiopsy acquisition in a sphere or throughout the entire placenta. We aimed to explore the relation between these two measurement methods. A prospective cohort study was conducted among normal pregnant women recruited at 11 to 40 gestational weeks. Placental vascularization was evaluated using the 3DPD indices (vascularization index [VI]; flow index [FI]; vascularization flow index [VFI]) with the application of the sphere ultrasound technique or scanned from the entire placenta. A total of 150 women were recruited at a mean gestational age of 20.8 ± 7.22 weeks. We observed that scanned 3DPD indices using sphere technique decrease by gestational age between 11 and 40 weeks, whereas whole placental volume scanning yielded stable, non-decreasing indices during gestation. The indices were correlated to each other at least moderately, irrespectively of the method of scanning (r≥0.30). As gestation advances, less and less placentas can be visualized in one sweep for a whole view and at late period of gestation only a minority of placentas can be visualized as a whole. 3DPD indices acquired in a sphere of the placenta at umbilical cord insertion may reflect more to the decreasing vascularity of the exponentially growing placenta during gestation. Hence, sphere technique may have a greater screening opportunity in pathological pregnancies. Orv Hetil. 2023; 164(8): 300-307.

Influence of corn supplementation to beef cows during mid- to late-gestation: Supplementation decreases placental microvascular surface density but does not alter uterine blood flow or neonatal performance1

Gestating cows fed low-quality forage diets are often at risk of nutrient restriction, including energy, protein, or both. Thus, the objective of this study was to evaluate the effects of supplementing corn to gestating beef cows fed low-quality forage by tracking uterine and mammary hemodynamics and neonatal performance. We hypothesized that mid- to late-gestating beef cows receiving corn supplementation would have enhanced uterine and mammary hemodynamics and increased placental microvascularity. At d 100 of gestation, multiparous cows, predominantly of Angus breeding, and carrying male calves were assigned randomly to the following treatments: supplementation (SUP; n = 24) at the level of 0.2% (dry matter basis) of body weight (BW) or basal diet without supplement (CON; n = 23). All cows were fed the same basal diet (60% hay, 30% wheat straw, and 10% concentrated separator by-product). Intake was monitored individually with Insentec feeders from d 100 of gestation through calving. Every 28 days from the beginning of supplementation at d 100 until d 240 of pregnancy, uterine and mammary hemodynamics were monitored using Doppler ultrasonography, and jugular blood samples were obtained to determine hormone concentrations. At birth (CON: 277.6 ± 3.1 days; SUP: 275.5 ± 2.8 days; mean ± stdev), cow and calf BW, colostrum samples, and placental tissues were collected. Representative cotyledons were excised from fetal membranes and histological image analysis of placental vascularity with hematoxylin and eosin staining was conducted. All measurements and data collected were analyzed with the MIXED procedure and means were separated using the LSMEANS statement in SAS. Hemodynamics, placental weight, and colostrum variables were not altered by supplementation (P ≥ 0.13). Placental microvascular surface density was suppressed (P < 0.01) by maternal corn supplementation. The differences in nutrient intake were not great enough to elicit differences in uterine or mammary hemodynamics, even though placental vascular surface density was decreased by corn supplementation in multiparous beef cows. Moreover, the few alterations in the maternal endocrine profiles due to corn supplementation did not translate into negative endocrine or early developmental changes in the offspring. Corn may be a good substitute for hay when costs and availability are economically advantageous to the producer.