Labyrinth Zone Research Articles

Antenatal pomegranate juice rescues hypoxia-induced fetal growth restriction in pregnant mice while reducing placental cell stress and apoptosis

IntroductionThere is a need for prophylaxis to reduce placental-associated intrauterine growth restriction (IUGR). Pomegranate juice (PJ) is replete with phytochemicals having biological effects at non-pharmacological concentrations. We test the hypothesis that exposure of pregnant mice to hypoxia late in gestation induces cellular stress in the placenta, which can be ameliorated by antecedent maternal consumption of PJ. Materials and methodsWe exposed pregnant mice to 12% or 21% oxygen, with food ad libitum or restricted, and with consumption of PJ or glucose between 12.5 and 18.5 days post conception (dpc). We examined the outcomes of the nine groups (n = 10) at 18.5 dpc, quantifying fetal and placental weights and placental labyrinthine and junctional zone depths and areas. We assayed cellular stress by expression of Hsp90 and apoptosis by TUNEL staining and expression of cleaved caspase 3. ResultsMaternal exposure to 12% oxygen or food restriction in 21% oxygen, induced IUGR, compared to control. The labyrinth to junctional zone ratio was lower in hypoxic ad libitum, compared to normoxic food-restricted, placentas. Antenatal PJ prior to and during hypoxic exposure significantly improved fetal growth, reduced Hsp90 expression, and limited apoptosis in the labyrinth, while enhancing junctional zone apoptosis. DiscussionMaternal exposure to hypoxia induces IUGR, cell stress, and apoptosis in mouse placentas. The labyrinth and junctional zone of the mouse placenta are differentially sensitive to FiO2 and to PJ. PJ offers benefits in the prophylaxis of IUGR in the mouse, but PJ effects on the junctional zone require further study.

Gestational changes in PRMT1 expression of murine placentas

IntroductionIn mammals, the placenta is an organ that is required to maintain the development of fetus during pregnancy. Although the proper formation of placenta is in part regulated by the post-translational modifications of proteins, little is known regarding protein arginine methylation during placental development. Here, we characterized developmental expression of protein arginine methyltransferase 1 (PRMT1) in mouse placentas. MethodsExpression levels of PRMT1 mRNA and protein in placentas were investigated using the real-time quantitative PCR and Western blot, respectively. Next, the localization of PRMT1 was determined by immunohistochemistry and immunofluorescence analyses. In addition, the levels of methylarginines of placental proteins were quantified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). ResultsPRMT1 mRNA and its protein were expressed at highest levels in mid-gestation stages, and their expression showed stepwise decrease in the late gestation. At embryonic (E) day 9, PRMT1 was observed in several different trophoblast cell (TC) subtypes. Furthermore, PRMT1 was mainly expressed in the labyrinth zone of TCs at E13. Finally, total methylarginines of proteins were significantly reduced in late gestation of placentas compared with mid-gestation stages. DiscussionIn this study, we found developmental changes in the placental expression of PRMT1 and in protein arginine methylation status during pregnancy. These findings provide fundamental information regarding placental PRMT1-mediated arginine methylation during the development.

PARTIAL PROGESTERONE DEPRIVATION ALTERS THE TRANSCRIPTION OF ESTROGEN RECEPTORS AND THEIR DOWNSTREAM GENES IN RAT PLACENTAS

ObjectiveTo investigate the role of progesterone in placental growth and effects on the expression of estrogen receptors‐alpha and ‐beta and their downstream genes.Materials and MethodsPregnant SD rats were segregated into A) control (peanut oil, twice daily injections), B) ovariectomized on 15 day gestation (dg), with progesterone restoration, and C) progesterone reduction groups. To restore estrogen levels, estradiol was administered subcutaneously using mini‐osmotic pump (40 ng/h) and then injected to maintain normal increase in plasma levels of the hormone. In group B, progesterone level was restored by administering the hormone daily and, in group C, progesterone reduction (partial deprivation) to one third of the normally observed level of the hormone on 22 dg was maintained. Placentas were harvested on 19 dg and 21 dg and dissected into basal and labyrinth zones. Gene expression of estrogen receptors‐alpha and ‐beta, p53, Bax and Bcl‐2 was analyzed by real time‐polymerase chain reaction. Data were analyzed by one way ANOVA and Least square difference test with the level of significance set p<0.05.ResultsPartial progesterone deprivation decreased placental and basal zone weights on 19 dg (p<0.05), which was not restored by progesterone restoration to normal levels. Progesterone restoration did not recover decreased fetal body weights in overiectomized rats although placental efficiency was not affected on 21 dg. Partial progesterone deprivation increased the transcription of both estrogen receptors in the basal zone on 19 dg (p<0.05), which recovered to normal levels after progesterone restoration. Similarly, p53, Bax and Bcl‐2 gene expressions were also increased in the basal zones in partial progesterone deprived rats, which were restored to normal levels on 19 dg and 21 dg, after progesterone restoration. A similar pattern was seen in the labyrinth zone on 16 dg and 19 dg.ConclusionPartial progesterone deprivation inhibits placental and fetal growth most probably by enhancing estrogen receptor‐mediated up‐regulation of apoptosis in placentas. Progesterone is essential for normal growth of placentas and fetuses in rats.Support or Funding InformationKuwait University Research Grant # MY02/08This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Hyperglycaemia in pregnancy disturbs maternal-foetal well-being and alters placental function: role of inflammatory markers fkn and rank/rankl/opg system

Event Abstract Back to Event Hyperglycaemia in pregnancy disturbs maternal-foetal well-being and alters placental function: role of inflammatory markers fkn and rank/rankl/opg system Noor E. Hashim1*, Mardhiah Tahir1, Intan S. Zulkafli1, Rasheeda Mohd. Zamin1 and Normadiah M Kassim1 1 University of Malaya, Malaysia Background Inflammation have been implicated for various diabetic complications. Fractalkine (FKN) and receptor activator of nuclear factor-kappaB ligand (RANKL)/RANK/osteoprotegerin (RANKL/RANK/OPG) systems are inflammatory markers suspected to be responsible for the changes seen in diabetic pregnancy. This study aimed to examine the effects of hyperglycaemia on pregnancy and investigate the role of these markers in the disease process. Methods Pregnant female Sprague-Dawley rats were injected with 45mg/kg BW of Streptozocin on gestational day (GD) 7 to induce diabetes followed by 10% glucose drink for 24h to prevent hypoglycaemic fatality. Control animals were injected with 1ml of citrate buffer vehicle. Diabetes was confirmed on GD15. Maternal weight and food intake were regularly monitored. Blood (maternal & foetal) and placenta separated into labyrinth and junctional zones were collected for morphological, biochemical and molecular analyses at GD15 and GD21. Results Maternal hyperglycaemia induced hyperphagia (p<0.05) and impeded maternal weight gain (p<0.05). Both groups were able to carry pregnancy to term but the hyperglycaemic group (HG) demonstrated trend towards increased foetal resorption at GD21 (13.6%, p=0.08) and 13.2% reduction of foetal weight (p<0.05). Although placenta weights were unchanged in all groups, feto-placental ratio dropped 15.8% in the HG group at GD21 (p<0.05). Morphologically, all placenta showed no significant differences in weight or thickness at both time points. Placenta zonal variations were observed in the mRNA expression of RANK, OPG, FKN and Vascular Endothelial Growth Factor A (VEGFa) but no hyperglycaemic effect was found. Conclusion This study demonstrated that maternal hyperglycaemia is detrimental in pregnancy through disruption of foetal survival (increased foetal resorption), disturbed maternal well-being (via altered eating pattern) and placental insufficiency through reduction of feto-placental ratio. Although expression of the inflammatory markers showed no significant role in the altered physiological milieu, more detailed studies are needed to delineate the exact role of these markers in hyperglycaemic pregnancy. Keywords: Maternal hyperglycaemia, Placenta, Pregnancy, Inflammatory markers, rat model Conference: International Conference on Drug Discovery and Translational Medicine 2018 (ICDDTM '18) “Seizing Opportunities and Addressing Challenges of Precision Medicine”, Putrajaya, Malaysia, 3 Dec - 5 Feb, 2019. Presentation Type: Poster Presentation Topic: Metabolic diseases Citation: Hashim NE, Tahir M, Zulkafli IS, Mohd. Zamin R and M Kassim N (2019). Hyperglycaemia in pregnancy disturbs maternal-foetal well-being and alters placental function: role of inflammatory markers fkn and rank/rankl/opg system. Front. Pharmacol. Conference Abstract: International Conference on Drug Discovery and Translational Medicine 2018 (ICDDTM '18) “Seizing Opportunities and Addressing Challenges of Precision Medicine”. doi: 10.3389/conf.fphar.2018.63.00005 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 05 Oct 2018; Published Online: 17 Jan 2019. * Correspondence: Dr. Noor E Hashim, University of Malaya, Kuala Lumpur, Malaysia, nooreliza@um.edu.my Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Noor E Hashim Mardhiah Tahir Intan S Zulkafli Rasheeda Mohd. Zamin Normadiah M Kassim Google Noor E Hashim Mardhiah Tahir Intan S Zulkafli Rasheeda Mohd. Zamin Normadiah M Kassim Google Scholar Noor E Hashim Mardhiah Tahir Intan S Zulkafli Rasheeda Mohd. Zamin Normadiah M Kassim PubMed Noor E Hashim Mardhiah Tahir Intan S Zulkafli Rasheeda Mohd. Zamin Normadiah M Kassim Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

The role of ACE2, angiotensin-(1\u20137) and Mas1 receptor axis in glucocorticoid-induced intrauterine growth restriction

BackgroundPlasma and urine levels of the potent vasodilator Ang-(1–7) are elevated in mid and late pregnancy and are correlated with elevated placental angiogenesis, fetal blood flow, and rapid fetal growth. We hypothesized that Ang-(1–7), its receptor (Mas1) and the enzymes involved in Ang-(1–7) production (ACE2 and Membrane metallo-endopeptidase; MME) are down regulated in response to glucocorticoid administration contributing to IUGR.MethodsPregnant female Sprague–Dawley rats were injected with dexamethasone (DEX; 0.4 mg/kg/day) starting from 14 day gestation (dg) till sacrifice at 19 or 21 dg while control groups were injected with saline (n = 6/group). The gene and protein expression of ACE2, MME, Ang-(1–7) and Mas1 receptor in the placental labyrinth (LZ) and basal zones (BZ) were studied. ResultsDEX administration caused a reduction in LZ weight at 19 and 21 dg (p < 0.001). IUGR, as shown by decreased fetal weights, was evident in DEX treated rats at 21 dg (p < 0.01). ACE2 gene expression was elevated in the LZ of control placentas at 21 dg (p < 0.01) compared to 19 dg and DEX prevented this rise at both gene (p < 0.01) and protein levels (p < 0.05). In addition, Ang-(1–7) protein expression in LZ was significantly reduced in DEX treated rats at 21 dg (p < 0.05). On the other hand, Mas1 and MME were upregulated in LZ at 21 dg in both groups (p < 0.05 and p < 0.001, respectively).ConclusionThe results of this study indicate that a reduced expression of ACE2 and Ang-(1–7) in the placenta by DEX treatment may be responsible for IUGR and consequent disease programming later in life.

Obesity-induced changes in hepatic and placental clock gene networks in rat pregnancy.

Maternal obesity induces pregnancy complications and disturbs fetal development, but the specific mechanisms underlying these outcomes are unclear. Circadian rhythms are implicated in metabolic complications associated with obesity, and maternal metabolic adaptations to pregnancy. Accordingly, obesity-induced circadian dysfunction may drive adverse outcomes in obese pregnancy. This study investigated whether maternal obesity alters the rhythmic expression of clock genes and associated nuclear receptors across maternal, fetal, and placental tissues. Wistar rats were maintained on a cafeteria (CAF) diet prior to and throughout gestation to induce maternal obesity. Maternal and fetal liver and placental labyrinth zone (LZ) were collected at four-hourly time points across days 15-16 and 21-22 of gestation (term = 23 days). Gene expression was analyzed by RT-qPCR. Expression of the accessory clock gene Nr1d1 was rhythmic in the maternal and fetal liver and LZ of chow-fed controls, but in each case CAF feeding reduced peak Nr1d1 expression. Obesity resulted in a phase advance (approx. 1.5 h) in the rhythms of several clock genes and Ppar-delta in maternal liver. Aside from Nr1d1, expression of clock genes was mostly arrhythmic in LZ and fetal liver, and was unaffected by the CAF diet. In conclusion, maternal obesity suppressed Nr1d1 expression across maternal, fetal, and placental compartments and phase-advanced the rhythms of maternal hepatic clock genes. Given the key role of Nr1d1 in regulating metabolic, vascular, and inflammatory processes, our data suggest that disruptions to rhythmic Nr1d1 expression in utero may contribute to programmed health complications in offspring of obese pregnancies.

PTHrP is essential for normal morphogenetic and functional development of the murine placenta

• PTHrP is expressed in the junctional and labyrinth zones of the murine placenta. • PTHrP is a regulator of placental development and function. • PTHrP influences trophoblast cell proliferation, survival and differentiation. • Fetal growth capacity is modulated by PTHrP. • Lack of PTHrP is associated with reduced placental system A transporter activity.

Dexamethasone-Induced Intrauterine Growth Restriction Is Associated With Altered Expressions of Metastasis Tumor Antigens and Cell Cycle Control Proteins in Rat Placentas.

Molecular mechanisms affecting placental formation in intrauterine growth-restricted (IUGR) pregnancies are not clearly understood. Since metastasis tumor antigens (MTAs) MTA1 and MTA2 promote cell proliferation and MTA3 suppresses it, we hypothesized that IUGR alters cell survival/cell death programs driven by placental MTAs. To induce IUGR, pregnant Sprague Dawley rats were given daily intraperitoneal injections of either saline or dexamethasone (0.4 mg/kg) starting from 14 days of gestation (dg) to either 19 dg or 21 dg. Gene and protein expressions of MTA1-3 in the placental basal and labyrinth zones were investigated by real-time polymerase chain reaction, Western blotting, and immunohistochemistry. We also explored the expressions of proliferating cell nuclear antigen (PCNA), caspase-3, p53, p21, and β-catenin. Dexamethasone-induced IUGR resulted in decreased expression of MTA1 in the nuclei of cells in the basal zone. The expression of p21 was increased and that of PCNA was reduced in both placental zones of IUGR rats. Cytoplasmic expression of MTA1 and p53 increased in the labyrinth zone of IUGR placentas in association with an increase in cell death as indicated by an increased caspase-3 expression. The labyrinth zone of IUGR placentas showed a significant reduction in MTA2-MTA3 gene expression and an increase in p53 protein levels. Total MTA3 level increased and β-catenin level decreased in the labyrinth zone of IUGR placentas associated with a reduction in cell proliferation. Taken together, these results strongly suggest that dexamethasone-induced IUGR is associated with changes in MTA expression, decreased cell proliferation, and increased cell death in placentas.

Evaluation of vascular effect of arsenic using in vivo assays.

Arsenic (As) is an abundant toxicant present in groundwater and soil in various parts of the world including eastern part of India. The epidemiological studies have shown that arsenic exposure is linked to developmental defects and miscarriage. Placenta is known to utilize vasculogenesis to develop its vasculature circulation. The effects of four different doses of sodium meta-arsenite (0, 10, 20, 75, and 150ppm) were assessed on the vascular structure using two different in vivo models, i.e., Matrigel and chorioallantoic membrane (CAM) assay. For the Matrigel assay, mice were exposed to different doses of arsenic through drinking water for 1month. Placenta and Matrigel plug (which was inserted on gestational day (GD 0.5)) were removed on GD 14. Similar arsenic concentration was used in CAM assay to observe the effect of vessel development in hen's eggs. The CAM assay outcome evaluated by Angiosys software showed that arsenic exposure reduced the total and mean tubule length in all the arsenic-treated groups. The percentage tubule inhibition was declined significantly in 20, 75, and 150ppm arsenic-treated groups as evaluated by ImageJ software. Analysis of the CAM outcome by both the image analysis software indicated the adverse effect of arsenic on the tubules. Further, a significant higher blood vessel density in 10ppm and lower vessel density in 20, 75, and 150ppm arsenic-exposed mice were also observed in Matrigel plug assay. The placental hypertrophy and dysplasia especially in the labyrinth zone (vasculature) were noted in placenta of arsenic-treated mice. The study indicated that higher arsenic exposures inhibited the angiogenesis which was dose-dependent in both CAM and Matrigel assay and altered structural morphology of placenta. However, no inhibition of blood vessels was noted at lower, i.e., 10ppm of arsenic-treated group.

EFFECT OF PRENATAL ADMINISTRATION OF THERAPEUTIC DOSE OF TOPIRAMATE ON PLACENTAE ALBINO RATS' FETUSES

Objective: Topiramate is an antiepileptic drug (AED) used for the treatment of partial seizure in adult and children epileptic patients. It passed through the placenta causing a birth defect. However, little literature focused on placental alteration due to the administration of topiramate during pregnancy. So, applying different predictive parameters; placental weight, histopathological (Haematoxylin and Eosin), histochemical (periodic acid Schiff’s) and immunohistochemistry (Caspase-3).Methods: Topiramate was orally administrated to the pregnant rats with dose 100 mg/kg rats from 5th to 19th day of gestation. The dam’s undergone hysterectomy and the placentae were weighted and stained by Haematoxylin and Eosin, periodic acid Schiff’s and Caspase-3. Results: The study indicated that there is statistically significant (P&lt;0.05) increase in the treated placental weight (0.4717±0.03788) compared with control group (0.5208±0.02930). Also, the light microscopic examination of the placental specimens using Haematoxylin and Eosin staining revealed that an alteration in both basal and labyrinth zone. Apoptotic feature in spongiotrophoblast and trophoblasts is detected. Positive Periodic acid Schiff’s reaction for polysaccharides in the topiramate-treated group. Caspase-3 is showing apoptotic cells in the trophoblast layer.Conclusion: Long-term daily use of topiramate during pregnancy can lead to obvious pathological histotoxic effects in layers of placenta tissues which may be implicated in cognitive affection. Various effects of topiramate necessitate further investigations.

Differential effects of chronic iron deficiency anaemia on junctional and labyrinthine zones of placenta in Sprague dawely rat

Iron deficiency anaemia causes adverse pregnancy outcome. Studies reveal its generalized effects on histomorphometry of the placenta, without details on specific zones nor effect of gestational age. These data are important for planning intervention. This study was, therefore, designed to describe the histomorphometric changes associated with iron deficiency anaemia on placenta of albino rat. Fourty nine (49) Sprague – Dawely albino rats were randomly separated into experimental and control groups. The experimental group was rendered anaemic by removing 1.5 ml of blood per bleed on five alternate days. Placentas were collected on gestational days 17, 19 and 21. Five cubic milimetre segments were fixed in 10 % buffered formaldehyde solution; dehydrated in ethanol and embedded in paraffin wax. Five micron thick sections were cut, deparaffinized and stained with Hematoxylin and Eosin. Micrographs were taken using Leica ICC 50 digital photomicrographic camera attached to a computer at magnification x40 and the thickness of the labyrinth and junctional zones measured. Student t- test was used to compare values for the experimental and control groups. The labyrinth in the chronic anaemia group was thinner than in the control group at gestational days 17, 19 and 21. The junctional zone, on the other hand, was consistently thicker in anaemic than in the control animals. The difference in thickness of junctional zone varied with gestational age. At gestational day 17, the zone was significantly thicker in the anaemic group (628.9 μ) than in the control (381 μ). On day 19 and 21, however, the difference was not statistically significant. In conclusion, the effects of chronic iron deficiency anaemia on the labyrinth differ from those on the junctional zone of the placenta. This differential effect appears to depend on the function and gestational age. The decrease in thickness of the labyrinth may be designed to maintain placental diffusion capacity while increased thickness of the junctional zone constitutes a compensatory physical and nutritional adaptation to hypoxia.Key words: placenta, labyrinthine, junctional zones, thickness, anaemia.

Competition for Materno-Fetal Resource Partitioning in a Rabbit Model of Undernourished Pregnancy.

The major goal of animal production is to obtain abundant and healthy meat for consumers. Maternal food restriction (MFR) is often applied in farms to reduce production costs. However, the suitability of MFR in livestock animals is questionable, as this management may compromise maternal fitness due to a severe negative energetic balance and can induce Intrauterine Growth Restriction (IUGR) and prenatal programming in the offspring. Here, we sought to determine, using pregnant rabbits, the consequences of MFR on maternal endocrine and metabolic status and conceptus development. Pregnant dams were distributed into three groups: CONTROL (ad libitum feeding throughout the entire pregnancy; mean pregnancy length being around 31 days), UNDERFED (50% MFR during the entire pregnancy) and EARLY-UNDERFED (50% MFR only during the preimplantation period, Days 0–7). Maternal leptin concentrations and glycemic and lipid profiles were determined throughout pregnancy, whilst conceptus development was assessed ex-vivo at Day 28. Placental parameters were determined by macroscopic and histological evaluations and apoptotic assessments (TUNEL and Caspase-3). The main results of the study showed that, despite MFR altered maternal plasma lipid concentration (P<0.05), there were no effects on maternal bodyweight, plasma leptin concentration or glycemic profile. Fetal crown-rump lengths were reduced in both undernourished groups (P<0.001), but a significant reduction in fetal weight was only observed in the UNDERFED group (P<0.001). Growth in both undernourished groups was asymmetrical, with reduced liver weight (P<0.001) and significantly increased brain: fetal weight-ratio (P<0.001) and brain: liver weight-ratio (P<0.001) when compared to the CONTROL group. A significant reduction in placental weight was only observed in the UNDERFED group (P<0.001), despite both undernourished groups showing higher apoptotic rates at decidua and labyrinth zone (P<0.05) than the CONTROL group. Thus, these groups evidenced signs of placental degeneration, necrosis and stromal collapse. In summary, MFR may encourage the mother to make strategic decisions to safeguard her metabolic status and fitness at the expense of growth reduction in the litter, resulting in enhanced apoptotic and pathological processes at placental level and IUGR.

Obeticholic Acid Protects against Lipopolysaccharide-Induced Fetal Death and Intrauterine Growth Restriction through Its Anti-Inflammatory Activity.

Farnesoid X receptor (FXR) is expressed in human and rodent placentas. Nevertheless, its function remains obscure. This study investigated the effects of obeticholic acid (OCA), a novel synthetic FXR agonist, on LPS-induced fetal death and intrauterine growth restriction. All pregnant mice except controls were i.p. injected with LPS (100 μg/kg) daily from gestational day (GD) 15 to GD17. Some pregnant mice were orally administered with OCA (5 mg/kg) daily from GD13 to GD17. As expected, placental FXR signaling was activated by OCA. OCA pretreatment protected against LPS-induced fetal death. In addition, OCA pretreatment alleviated LPS-induced reduction of fetal weight and crown-rump length. Additional experiments showed that OCA inhibited LPS-evoked TNF-α in maternal serum and amniotic fluid. Moreover, OCA significantly attenuated LPS-induced upregulation of placental proinflammatory genes including Tnf-α, Il-1β, IL-6, Il-12, Mip-2, Kc, and Mcp-1 By contrast, OCA elevated anti-inflammatory cytokine IL-10 in maternal serum, amniotic fluid, and placenta. Further analysis showed that OCA blocked nuclear translocation of NF-κB p65 and p50 subunits in trophoblast giant cells of the labyrinth zone. These results provide a mechanistic explanation for placental FXR-mediated anti-inflammatory activity. Overall, this study provides evidence for roles of FXR as an important regulator of placental inflammation.

ARID3A is required for mammalian placenta development

Previous studies in the mouse indicated that ARID3A plays a critical role in the first cell fate decision required for generation of trophectoderm (TE). Here, we demonstrate that ARID3A is widely expressed during mouse and human placentation and essential for early embryonic viability. ARID3A localizes to trophoblast giant cells and other trophoblast-derived cell subtypes in the junctional and labyrinth zones of the placenta. Conventional Arid3a knockout embryos suffer restricted intrauterine growth with severe defects in placental structural organization. Arid3a null placentas show aberrant expression of subtype-specific markers as well as significant alteration in cytokines, chemokines and inflammatory response-related genes, including previously established markers of human placentation disorders. BMP4-mediated induction of trophoblast stem (TS)-like cells from human induced pluripotent stem cells results in ARID3A up-regulation and cytoplasmic to nuclear translocation. Overexpression of ARID3A in BMP4-mediated TS-like cells up-regulates TE markers, whereas pluripotency markers are down-regulated. Our results reveal an essential, conserved function for ARID3A in mammalian placental development through regulation of both intrinsic and extrinsic developmental programs.

The effects of Nrf2 deletion on placental morphology and exchange capacity in the mouse

Objectives: Intrauterine growth restriction (IUGR) is defined as a pathological decreased fetal growth. Oxidative stress has been connected to the restriction in the fetal growth. The transcription factor nuclear factor-erythroid 2-related factor 2 (Nrf2) is a potent activator of the cellular antioxidant response. The effect Nrf2 on fetal–placental development has not yet been sufficiently investigated. Here, we evaluated the placental and fetal growth in Nrf2 knockout (Nrf2-KO) and Nrf2-wild type mice (Nrf2-WT) throughout pregnancy. Methods: Heterozygote Nrf2 (Nrf2+/−) mice were paired to get Nrf2-KO and Nrf2-WT in the litters. Placentae and embryos from both genotypes were collected and weighed on days 13.5, 15.5 and 18.5 post coitum. The absolute volumes of the labyrinth zone and the total volume of the placenta were determined using the Cavalieri principle. Results: On E 18.5 the fetal weight in Nrf2-KO was significantly reduced versus Nrf2-WT indicating a decrease in placental efficiency. A significant reduction in both total and labyrinth-volume in the placenta of Nrf2-KO mice was observed. Conclusion: This data points out the necessity of functional Nrf2 for fetal and placental growth. A deficiency in Nrf2 signaling may negatively affect nutrient transfer capacity which is then no longer able to meet fetal growth demands.

Carbenoxolone exposure during late gestation in rats alters placental expressions of p53 and estrogen receptors

Gestational carbenoxolone exposure inhibits placental 11β-hydroxysteroid dehydrogenase (11β-HSD), the physiological barrier for glucocorticoids, which increases fetal exposure to glucocorticoids and induces intrauterine growth restriction (IUGR). We hypothesized that carbenoxolone exposure influences the expression of placental estrogen receptors-α and β (ERα & ERβ) and p53 leading to inhibited fetal and placental growth. Pregnant Sprague-Dawley rats were injected twice daily with either carbenoxolone (10mg/kg; s.c.) or vehicle (control group) from gestational days (dg) 12 onwards. Maternal blood and placentas were collected on 16 dg, 19 dg and 21 dg. The expression of ERα, ERβ and p53 were studied in placental basal and labyrinth zones by RT-PCR, Western blotting and immunohistochemistry. Carbenoxolone did not affect placental and fetal body weights, but ELISA showed decreased estradiol levels on 19 dg and 21 dg, and increased maternal luteinizing hormone levels on all dg. The follicle stimulating hormone levels decreased on 16 dg and 19 dg, and increased on 21 dg. Carbenoxolone decreased ERα mRNA levels on 16 dg in both zones and its protein level on 19 dg in the labyrinth zone. However, carbenoxolone increased ERβ mRNA levels on 19 dg and 21 dg and protein levels on 16 dg and 19 dg in the labyrinth zone. The p53 mRNA levels increased on all dg, but its protein levels increased on 21 dg in both zones. In conclusion, carbenoxolone exposure changes placental p53, ERα, ERβ expression in favor of cell death but these changes do not induce IUGR in rats.

Morphology, histochemistry and glycosylation of the placenta and associated tissues in the European hedgehog (Erinaceus europaeus)

IntroductionThere are few descriptions of the placenta and associated tissues of the European hedgehog (Erinaceus europaeus) and here we present findings on a near-term pregnant specimen. MethodsTissues were examined grossly and then formalin fixed and wax-embedded for histology and immunocytochemistry (cytokeratin) and resin embedded for lectin histochemistry. ResultsEach of four well-developed and near term hoglets displayed a discoid, haemochorial placenta with typical labyrinth and spongy zones. In addition there was a paraplacenta incorporating Reichert's membrane and a largely detached yolk sac. The trophoblast of the placenta contained diverse populations of granule which expressed most classes of glycan. Intercellular membranes were also glycosylated and this tended to be heavier in the labyrinth zone. Fetal capillary endothelium had glycosylated apical surfaces expressing sialic acid and various other glycans. Glycogen was present in large cells situated between the spongy zone and the endometrium. Trophoblast cells in the placental disc and under Reichert's membrane, as well as yolk sac endoderm and mesothelium, were cytokeratin positive. Reichert's membrane was heavily glycosylated. Yolk sac inner and outer endoderm expressed similar glycans except for N-acetylgalactosamine residues in endodermal acini. DiscussionNew features of near-term hedgehog placenta and associated tissues are presented, including their glycosylation, and novel yolk sac acinar structures are described. The trophoblast of the placental disc showed significant differences from that underlying Reichert's membrane while the glycan composition of the membrane itself showed some similarity to that of rat thereby implying a degree of biochemical conservation of this structure.

Alcohol exposure impairs trophoblast survival and alters subtype-specific gene expression in vitro

Maternal alcohol consumption is common prior to pregnancy recognition and in the rat results in altered placental development and fetal growth restriction. To assess the effect of ethanol (EtOH) exposure on the differentiation of trophoblast stem (TS) cells, mouse TS lines were differentiated in vitro for 6 days in 0%, 0.2% or 1% EtOH. This reduced both trophoblast survival and expression of labyrinth and junctional zone trophoblast subtype-specific genes. This suggests that fetal growth restriction and altered placental development associated with maternal alcohol consumption in the periconceptional period could be mediated in part by direct effects on trophoblast development.

Chromium VI − Induced developmental toxicity of placenta is mediated through spatiotemporal dysregulation of cell survival and apoptotic proteins

Environmental contamination with hexavalent chromium (CrVI) is a growing problem both in the U.S and developing countries. CrVI is a heavy-metal endocrine disruptor; women working in Cr industries exhibit an increased incidence of premature abortion and infertility. The current study was designed to understand the mechanism of CrVI toxicity on placental cell survival/death pathways. Pregnant mothers were treated with or without CrVI (50ppmK2Cr2O7) through drinking water from gestational day (GD) 9.5–14.5, and placentas were analyzed on GD 18.5. Results indicated that CrVI increased apoptosis of trophoblasts, vascular endothelium of the metrial glands and yolk sac epithelium through caspase-3 and p53-dependent pathways. CrVI increased apoptosis in labyrinth and basal zones in a caspase-3-independent manner via AIF, and through an ATM-p53-NOXA-PUMA-p27 network. CrVI downregulated cell survival proteins Bcl-2, Bcl-XL and XIAP in the placenta. CrVI disrupts placental histoarchitecture and increases cell death by spatiotemporal modulation of apoptotic signaling.

Effect of selective fetectomy on morphology of the mouse placenta

IntroductionPlacental examination is recommended when genetic mutations cause fetal lethality in mice. But how fetal death alters histomorphology of the surviving mouse placenta is not known. MethodsPlacentas were examined at E17.5 after fetectomy of 1–2 fetal mice per pregnancy at either embryonic day (E) 15.5 (N = 8; Fx-2 group) or E13.5 (N = 5; Fx-4 group), which left 12 ± 2 surviving fetuses per litter. ResultsFetectomy caused no changes in placental weights and no increases in placental hypoxia (pimonidazole staining). The size and cell morphology of the decidua and junctional zone regions were unchanged and, in the Fx-2 group, these regions became significantly less hypoxic. Significant changes in labyrinth volume included a 30% increase in the Fx-2 group and in both groups, a >50% decrease in % fetal blood space and >40% increase in % labyrinth tissue. Maternal blood sinusoid volume was unchanged. Cell death in the labyrinth was significantly increased (22-fold increase in TUNEL staining) whereas placental mRNA expression of the proliferation marker Mki67 was unchanged. mRNA expression of sFlt1 and Prl3b1 (mPL-II) was unchanged in the labyrinth and junctional zone tissues in the Fx-2 group and in whole placental tissue in the Fx-4 group. DiscussionPlacental examination of the junctional zone and decidual regions after spontaneous fetal death in late gestation is likely to yield useful phenotypic information and abnormalities that may contribute to fetal death. In contrast, labyrinth abnormalities including increased tissue volume and reduced fetoplacental vascularity may not be due to genetic perturbation nor predate fetal death.