Placental Underperfusion in a Rat Model of Intrauterine Growth Restriction Induced by a Reduced Plasma Volume Expansion

Lower maternal plasma volume expansion was found in idiopathic intrauterine growth restriction (IUGR) but the link remains to be elucidated. An animal model of IUGR was developed by giving a low-sodium diet to rats over the last week of gestation. This treatment prevents full expansion of maternal circulating volume and the increase in uterine artery diameter, leading to reduced placental weight compared to normal gestation. We aimed to verify whether this is associated with reduced remodeling of uteroplacental circulation and placental hypoxia. Dams were divided into two groups: IUGR group and normal-fed controls. Blood velocity waveforms in the main uterine artery were obtained by Doppler sonography on days 14, 18 and 21 of pregnancy. On day 22 (term = 23 days), rats were sacrificed and placentas and uterine radial arteries were collected. Diameter and myogenic response of uterine arteries supplying placentas were determined while expression of hypoxia-modulated genes (HIF-1α, VEGFA and VEGFR2), apoptotic enzyme (Caspase -3 and -9) and glycogen cells clusters were measured in control and IUGR term-placentas. In the IUGR group, impaired blood velocity in the main uterine artery along with increased resistance index was observed without alteration in umbilical artery blood velocity. Radial uterine artery diameter was reduced while myogenic response was increased. IUGR placentas displayed increased expression of hypoxia markers without change in the caspases and increased glycogen cells in the junctional zone. The present data suggest that reduced placental and fetal growth in our IUGR model may be mediated, in part, through reduced maternal uteroplacental blood flow and increased placental hypoxia.     

Morphometric analysis of terminal villi and gross morphological changes in the placentae of term idiopathic intrauterine growth restriction

The aim of this study is to compare the gross morphology of the placentae and the morphometry of terminal villi and terminal villous capillaries in pregnancies complicated by idiopathic intrauterine growth restriction (IUGR) with those of normal pregnancies. 75 placentae were collected between April 2010 and March 2011. 50 placentae were associated with idiopathic IUGR and 25 were from controls. Insertion of cords, placental weights and diameters were noted. Hematoxylin and eosin-stained wax sections were analyzed stereologically. Growth of terminal villi and fetal capillaries was assessed by estimating total and mean surface areas. Villous capillarization was monitored using capillary:villus surface ratio. Measurements were done using image analysis system. In comparison with the control group, idiopathic IUGR placentae are significantly smaller (p = 0.000) and lighter (p = 0.000). In majority of IUGR (68%) and control (60%) cases, eccentric insertion of cord is noted. In idiopathic IUGR group, there is a significant decrease in the total areas of both terminal villi (p = 0.048) and their capillaries (p = 0.000) and a significant decrease in number of both terminal villi (p = 0.000) and their capillaries (p = 0.001), also, capillarization index is significantly smaller (p = 0.038). Idiopathic IUGR is associated with reduced growth of placental terminal villi and fetal capillaries and this is accompanied by changes in measures of villous capillarization as compared with those of control placentae. Further investigations of idiopathic IUGR placentae are necessary, especially considering the histopathological changes that could affect the fetomaternal exchange, with a note that strict distinction should be made between idiopathic and nonidiopathic IUGR placentae.     

Induction of intrauterine growth restriction by reducing placental vascular growth with the angioinhibin TNP-470

The placenta is a specialized vascular interface between the maternal and fetal circulations that increases in size to accommodate the nutritional and metabolic demands of the growing fetus. Vascular proliferation and expansion are critical components of placental development and, consequently, interference with vascular growth has the potential to severely restrict concurrent development of both the placenta and fetus. In this study, we describe the effects of an antiangiogenic agent, TNP-470, on placental vascular development and the induction of a form of intrauterine growth restriction (IUGR) in mice. Administration of TNP-470 to dams in the second half of pregnancy resulted in a smaller maternal weight gain accompanied by decreased placental and fetal sizes in comparison with control animals. Total numbers of fetuses per litter were not affected significantly. Stereological analysis of placentas revealed no changes in the combined lengths of vessels. However, the mean cross-sectional areas of maternal and fetal vessels in the labyrinth of TNP-470-treated mice were reduced at Embryonic Day 13.5 (E13.5) but not at E18.5. Further analysis showed reduced placental endothelial proliferation at E13.5 and E18.5 in TNP-470-treated animals. No other structural or morphometric differences in placentas were detected between TNP-470-treated and control mice at E18.5. This study provides conclusive evidence that administration of TNP-470 interferes with placental vascular proliferation and vessel caliber and results in a reproducible model of IUGR.     

Effects of embryo culture on angiogenesis and morphometry of bovine placentas during early gestation

The objective of this study was to determine the effects of undefined and semidefined culture systems for in vitro embryo production on angiogenesis and morphometry of bovine placentas during early gestation. Blastocysts produced in vivo were recovered from superovulated Holstein cows and served as controls. Blastocysts produced in vitro were exposed to either serum-supplemented medium with cumulus cell coculture (in vitro-produced with serum; IVPS) or modified synthetic oviductal fluid medium without serum or coculture (mSOF). Single blastocysts from each production system were transferred into heifers. Fetuses and placentas were recovered on Day 70 of gestation. Cotyledonary tissues were obtained for quantification of vascular endothelial growth factor (VEGF) and peroxisome proliferator-activated receptor-gamma (PPARG) mRNA and protein. Samples of placentomes were prepared for immunocytochemistry and histological analysis. Placentas from the mSOF group were heavier and had the fewest placentomes, least placental fluid, and lowest placental efficiency (fetal weight/placental weight) compared with the in vivo and IVPS groups. There was no effect of embryo culture system on volume densities of fetal villi or maternal endometrium within placentomes. The volume density of fetal pyknotic cells was increased in placentomes in the mSOF group compared with the in vivo and IVPS groups. Placentomes in the mSOF group had decreased densities of blood vessels and decreased levels of VEGF mRNA in cotyledonary tissue. In conclusion, compared with placentas from embryos produced in vivo or in vitro using an undefined culture system, placentas from embryos produced in vitro using a semidefined culture system exhibited a greater degree of aberrant development of the placenta during early gestation.     

Survival and size are differentially regulated by placental and fetal PKBalpha/AKT1 in mice

The importance of placental circulation is exemplified by the correlation of placental size and blood flow with fetal weight and survival during normal and compromised human pregnancies in such conditions as preeclampsia and intrauterine growth restriction (IUGR). Using noninvasive magnetic resonance imaging, we evaluated the role of PKBalpha/AKT1, a major mediator of angiogenesis, on placental vascular function. PKBalpha/AKT1 deficiency reduced maternal blood volume fraction without affecting the integrity of the fetomaternal blood barrier. In addition to angiogenesis, PKBalpha/AKT1 regulates additional processes related to survival and growth. In accordance with reports in adult mice, we demonstrated a role for PKBalpha/AKT1 in regulating chondrocyte organization in fetal long bones. Using tetraploid complementation experiments with PKBalpha/AKT1-expressing placentas, we found that although placental PKBalpha/AKT1 restored fetal survival, fetal PKBalpha/AKT1 regulated fetal size, because tetraploid complementation did not prevent intrauterine growth retardation. Histological examination of rescued fetuses showed reduced liver blood vessel and renal glomeruli capillary density in PKBalpha/Akt1 null fetuses, both of which were restored by tetraploid complementation. However, bone development was still impaired in tetraploid-rescued PKBalpha/Akt1 null fetuses. Although PKBalpha/AKT1-expressing placentas restored chondrocyte cell number in the hypertrophic layer of humeri, fetal PKBalpha/AKT1 was found to be necessary for chondrocyte columnar organization. Remarkably, a dose-dependent phenotype was exhibited for PKBalpha/AKT1 when examining PKBalpha/Akt1 heterozygous fetuses as well as those complemented by tetraploid placentas. The differential role of PKBalpha/AKT1 on mouse fetal survival and growth may shed light on its roles in human IUGR.     

Angiogenesis and morphometry of bovine placentas in late gestation from embryos produced in vivo or in vitro

The objective of this study was to determine the effects of in vitro embryo production on angiogenesis and morphometry of the bovine placenta during late gestation. Blastocysts produced in vivo were recovered from superovulated Holstein cows. Blastocysts produced in vitro were obtained after culture of in vitro-matured and -fertilized Holstein oocytes. Single blastocysts from each production system were transferred into heifers. Fetuses and placentas were recovered on Day 222 of gestation (in vivo, n=12; in vitro, n=12). Cotyledonary and caruncular tissues were obtained for quantification of vascular endothelial growth factor (VEGF) and peroxisome proliferator-activated receptor-gamma (PPARgamma) mRNA and protein. Tissue sections of placentomes were prepared for morphometric analysis. Fetuses and placentas were heavier from embryos produced in vitro than from embryos produced in vivo. More placentas from embryos produced in vitro had an excessive volume of placental fluid. There was no effect of treatment on the expression of mRNA for VEGF and PPARgamma in either cotyledonary or caruncular tissues. The expression of VEGF protein in cotyledons and caruncles as well as the expression of PPARgamma protein in cotyledons were not different between the in vitro and in vivo groups. However, caruncles from the in vitro group had increased expression of PPARgamma protein. The total surface area of endometrium was greater for the in vitro group compared with controls. In contrast, the percentage placentome surface area was decreased in the in vitro group. Fetal villi and binucleate cell volume densities were decreased in placentomes from embryos produced in vitro. The proportional tissue volume of blood vessels in the maternal caruncles was increased in the in vitro group. Furthermore, the ratios of blood vessel volume density-to-placentome surface area were increased in the in vitro group. In conclusion, these findings are consistent with the concept that compensatory mechanisms exist in the vascular beds of placentas from bovine embryos produced in vitro.     

Intrauterine growth retardation in experimental diabetes: possible role of the placenta

Fetal growth disorders are common in pregnancy complicated by diabetes. Whereas macrosomia often occurs in infants of diabetic women, growth retardation is almost a rule in spontaneous and experimental diabetes in animals. However, it is not clear when during development growth inhibition starts and how placental pathology might affect fetal growth in maternal diabetes. In this study pregnant Wistar rats were injected (ip) with a single dose of 50 mg/kg of streptozotocin (STZ) on gestation day (GD) 2 and a blood glucose level of 200 mg/dl or more determined 24 hrs later indicated diabetes. The controls were non-treated, buffer treated or, following confirmation of diabetes, injected with a single dose of 2--6 IU of insulin (Novo Ultralente) once daily. Fetuses and placentae were collected from GD 14--20. Intrauterine growth retardation (IUGR) in STZ group was significant as early as GD 15 and persisted to GD 20. Insulin produced a significant recovery in fetal weight gain. The placentas of STZ-treated group were significantly heavier than those of the control groups. The reduction in cord length of the STZ group became apparent on GD 16 and remained so to term. The placenta of GD 14 STZ group had a thicker decidua basalis and dilated maternal sinusoids. By GD 16, the decidua basalis contained glycogen-containing decidual cells and scattered glycogen cells confirmed by Best's carmine with or without diastase. The glycogen cells of the basal zone were more abundant, and had degenerated in some sites leaving behind cysts with eosinophilic mass. The giant cells had proliferated enormously. The labyrinthine zone appeared spongy with persistent fetal mesenchyme, peri-vascular fibrosis, and enhanced placental barrier. The trophoblasts of the labyrinths also contained traces of glycogen unlike the controls. By GD 18, the decidua basalis of the STZ group was thinner than that of the controls and contained necrotic giant cells and lymphocytic aggregations. In the basal zone, the giant cells had proliferated further; more glycogen cells had degenerated. Perivascular fibrosis was still extensive in the labyrinthine zone. Bloodless maternal sinusoids, extensive vacuolization, degeneration of glycogen islands and formation of cysts characterized the labyrinthine zone. These changes varied in intensity from one area to another in the same placenta and between placentas of the same and of different litters. The development of the upper and lower jaws, elevation and fusion of palatal shelves, reduction of physiological umbilical hernia, descent of the testes, fusion of the urethral folds and separation of digits of the paws were significantly delayed in the STZ group. The consistent association of placental pathology with fetal growth retardation is suggestive of an alteration in placental function possibly contributing to IUGR in STZ-induced diabetes in rats.     

Human placental transthyretin in fetal growth restriction in combination with preeclampsia and the HELLP syndrome

Fetal growth restriction is a serious, still poorly understood pregnancy-related pathology often associated with preeclampsia. Recent studies speculate on the role of human transthyretin, a carrier protein for thyroxin and retinol binding protein, in the etiology of both pregnancy pathologies. Objective was to investigate the localization and abundance of transthyretin (TTR) in placentas of pregnancies suffering from fetal growth restriction with and without preeclampsia and HELLP. This was a retrospective case control study on human paraffin-embedded placentas from pregnancies with a gestational age at delivery between the 24th and 34th week of gestation. 16 placentas were included in this study, 11 cases and 5 from normotensive pregnancies as controls. Cases were divided into three groups: four from early onset idiopathic intrauterine growth restriction (IUGR), four from early-onset severe preeclampsia (PE), and three from early-onset IUGR with preeclampsia plus HELLP syndrome. Distribution and abundance of TTR were investigated by means of immunohistochemistry. Semi quantitative analysis of TTR staining of placental sections revealed that TTR was mostly expressed in the villous trophoblast covering placental villi. Only weak staining of TTR in villous stroma could be detected. The comparison of placentas revealed that in pure IUGR and severe PE there is a much stronger TTR reactivity compared to controls and cases with IUGR?+?PE?+?HELLP. Concluding, the study showed that TTR is dysregulated in cases of IUGR and severe early onset preeclampsia. Interestingly, TTR expression is not affected in cases with HELLP syndrome that reveal the same staining intensities as age-matched controls.     

Down-regulation of placental folate transporters in intrauterine growth restriction

Folate deficiency in pregnancy is associated with neural tube defects, restricted fetal growth and fetal programming of diseases later in life. Fetal folate availability is dependent on maternal folate levels and placental folate transport capacity, mediated by two key transporters, Folate Receptor-α and Reduced Folate Carrier (RFC). We tested the hypothesis that intrauterine growth restriction (IUGR) is associated with decreased folate transporter expression and activity in isolated syncytiotrophoblast microvillous plasma membranes (MVM). Women with pregnancies complicated by IUGR (birth weight <3rd percentile, mean birth weight 1804±110 g, gestational age 35.7±0.61 weeks, n=25) and women delivering an appropriately-for gestational age infant (control group, birth weight 25th–75th centile, mean birth weight 2493±216 g, gestational age 33.9±0.95 weeks, n=19) were recruited and placentas were collected at delivery. MVM was isolated and folate transporter protein expression was measured using Western blot and transporter activity was determined using radiolabelled methyltetrahydrofolic acid and rapid filtration. Whereas the expression of FR-α was unaffected, MVM RFC protein expression was significantly decreased in the IUGR group (−34%, P<.05). IUGR MVM had a significantly lower folate uptake compared to the control group (−38%, P<.05). In conclusion, placental folate transport capacity is decreased in IUGR, which may contribute to the restricted fetal growth and intrauterine programming of childhood and adult disease. These findings suggest that continuation of folate supplementation in the second and third trimester is of particular importance in pregnancies complicated by IUGR.     

Orally Administered Melatonin Prevents Lipopolysaccharide-Induced Neural Tube Defects in Mice

Lipopolysaccharide (LPS) has been associated with adverse pregnant outcomes, including fetal demise, intra-uterine growth restriction (IUGR), neural tube defects (NTDs) and preterm delivery in rodent animals. Previous studies demonstrated that melatonin protected against LPS-induced fetal demise, IUGR and preterm delivery. The aim of the present study was to investigate the effects of melatonin on LPS-induced NTDs. All pregnant mice except controls were intraperitoneally injected with LPS (25 µg/kg) daily from gestational day (GD)8 to GD12. Some pregnant mice were orally administered with melatonin (MT, 50 mg/kg) before each LPS injection. A five-day LPS injection resulted in 27.5% of fetuses with anencephaly, exencephaly or encephalomeningocele. Additional experiment showed that maternal LPS exposure significantly down-regulated placental proton-coupled folate transporter (pcft) and disturbed folate transport from maternal circulation through the placentas into the fetus. Interestingly, melatonin significantly attenuated LPS-induced down-regulation of placental pcft. Moreover, melatonin markedly improved the transport of folate from maternal circulation through the placentas into the fetus. Correspondingly, orally administered melatonin reduced the incidence of LPS-induced anencephaly, exencephaly or encephalomeningocele. Taken together, these results suggest that orally administered melatonin prevents LPS-induced NTDs through alleviating LPS-induced disturbance of folate transport from maternal circulation through the placenta into the fetus.     

The expression of Akt and ERK1/2 proteins decreased in dexamethasone-induced intrauterine growth restricted rat placental development

The placenta is a complicated tissue that lies between maternal and fetal compartments. Although the architecture of the human and rodent placentas differ a little in their details, their overall structures and the molecular mechanisms of placental developments are thought to be very similar. In rats, fetal–placental exposure to maternally administered glucocorticoids decreases birth weight and placental weight. The mechanism underlying the placental growth inhibitory effects of glucocorticoids have not been elucidated. Moreover it is still not determined that how Akt and ERK1/2 proteins related proliferation and apoptosis mechanisms are influenced by dexamethasone-induced IUGR (Intrauterine Growth Restriction) placentas. The aim of this study was to investigate the expression levels and spatio-temporal immunolocalizations of Akt, p-Akt, ERK1/2 and p-ERK1/2 proteins in normal and dexamethasone treated placental development in pregnant Wistar rats. Pregnant rats were subcutaneously injected with 100 μg/kg dexamethasone 21-acetate in 0.1 ml 10% ethanol on day 10 and 12 of gestation. Afterwards injection was continued as 200 μg/kg until they were killed on day 12 (injection started on day 10), 14, 16, 18 and 20 (injections started on day 12) of pregnancy. Placental and embryonal tissues were collected for immunohistochemistry and Western blot analysis. We found that maternal dexamethasone treatment led to a decrease in ERK1/2 and Akt activation during rat placental development. The decrease in Akt and ERK1/2 activations may result with cell survival inhibition or apoptosis stimulation. Hence, dexamethasone induced placental and embryonal developmental abnormalities could be associated with reduction of Akt and ERK1/2 activation.     

Antioxidants activities and concentration of selenium,zinc and copper in preterm and IUGR human placentas

The aim of this study was to examine changes in activities of cytochrome c oxidase (CCO), glucose-6-phosphate dehydrogenase (G6PDH), Cu–Zn superoxide dismutase (Cu–Zn SOD), glutathione peroxidase (GSH-Px), glutathione (GSH) levels and copper (Cu), zinc (Zn) and selenium (Se) concentrations, and to assess the possible differences between preterm placentas, placentas from term pregnancies complicated by intrauterine growth restriction (IUGR) and full-term control placentas.The enzyme activities and the level of GSH decreased in IUGR and preterm placentas in comparison with the control group. CCO activity and GSH level in preterm placentas were markedly lower compared with the IUGR (P<0.01; P<0.05) and control (P<0.01; P<0.05) placentas, respectively. In IUGR placentas the level of Cu was reduced by 23% (P<0.05) and Zn by 37%. In preterm placentas the level of Cu was reduced by 19% and Zn by 42%. Se level in IUGR and preterm placentas was higher (P<0.05) by 28% and 32% than in control group, respectively. The strong relation was observed between birth weight and CCO activity, birth weight and Cu–Zn SOD activity, and a low level of Zn and Cu influenced the birth weight especially in IUGR cases. Moreover, the strong inverse correlation between Se level and birth weight, Se level and placental weight and Se level and CCO activity are new findings.     

Molecular evidence suggesting the persistence of residual SARS‐CoV‐2 and immune responses in the placentas of pregnant patients recovered from COVID‐19

ObjectivesRecent studies have shown the presence of SARS‐CoV‐2 in the tissues of clinically recovered patients and persistent immune symptoms in discharged patients for up to several months. Pregnant patients were shown to be a high‐risk group for COVID‐19. Based on these findings, we assessed SARS‐CoV‐2 nucleic acid and protein retention in the placentas of pregnant women who had fully recovered from COVID‐19 and cytokine fluctuations in maternal and foetal tissues.Materials and MethodsRemnant SARS‐CoV‐2 in the term placenta was detected using nucleic acid amplification and immunohistochemical staining of the SARS‐CoV‐2 protein. The infiltration of CD14+ macrophages into the placental villi was detected by immunostaining. The cytokines in the placenta, maternal plasma, neonatal umbilical cord, cord blood and amniotic fluid specimens at delivery were profiled using the Luminex assay.ResultsResidual SARS‐CoV‐2 nucleic acid and protein were detected in the term placentas of recovered pregnant women. The infiltration of CD14+ macrophages into the placental villi of the recovered pregnant women was higher than that in the controls. Furthermore, the cytokine levels in the placenta, maternal plasma, neonatal umbilical cord, cord blood and amniotic fluid specimens fluctuated significantly.ConclusionsOur study showed that SARS‐CoV‐2 nucleic acid (in one patient) and protein (in five patients) were present in the placentas of clinically recovered pregnant patients for more than 3 months after diagnosis. The immune responses induced by the virus may lead to prolonged and persistent symptoms in the maternal plasma, placenta, umbilical cord, cord blood and amniotic fluid.     

Histomorphometric parameters and fractal complexity of the equine placenta from healthy and sick foals

Computer-based digital image analysis of tissue samples shows promise both to reduce the subjectivity of traditional manual tissue assessments and potentially to shorten the time required to analyze each sample. The present study used digital image analysis to investigate the histomorphometric parameters and fractal complexity of the equine placenta from healthy and sick foals. We hypothesized that the placentas of sick foals could have a different growth pattern and complexity that could be objectively estimated by their fractal dimension (FD). Fourteen placentas from 30 mares were selected in the 2013 breeding season and divided into two groups: seven mares with normal pregnancy, eutocic delivery, and healthy foals (group 1) and seven mares with normal or high-risk pregnancy, eutocic delivery and sick foals (group 2). Four mares in group 2 were classified as having a high-risk pregnancy on the basis of anamnesis and/or ultrasound findings. Clinical diagnosis of group 2 foals included perinatal asphyxia syndrome (n = 4), prematurity/dysmaturity (n = 2), and both diagnoses (n = 1). Seven out of fourteen placentas showed diffuse gross abnormalities. Grossly abnormal placentas were observed in one out of seven (14.28%) animals in group 1 and in six out of seven (85.72%) animals in group 2. Digital image analysis proved to be reliable and efficient in segmentation, calculation, outline extraction of villi as also resulted in sampled test images. The placentas of group 1 foals displayed a uniform and homogeneous villi development, as revealed by geometric parameters and FD. These results can be interpreted as a harmonic growth pattern of microcotyledons throughout the placenta in healthy foals. By contrast, the placentas of group 2 foals showed a nonuniform growth pattern and complexity with more villi and more developed villi in pregnant horn (PH) and nonpregnant horn (NPH) compared with body (B) and higher FD in NPH than in the other areas. This finding can be interpreted as a compensatory growth with increased complexity. Our results show that morphometric analysis, particularly FD measurement, can be proposed as an ancillary histological tool for equine placenta evaluation. Chorionic villi tend to have greater branching and complexity in sick than in healthy foals, particularly in the NPH. This could represent an attempt to increase the exchange area between fetal and maternal compartments of the equine placenta, and merits further investigation.     

The effect of maternal undernutrition on the growth and development of the guinea pig placenta.

Fetal growth is known to be correlated with the size of the placenta and the exchange surface area. Reduction in the growth of the materno-fetal exchange surface areas may be a mechanism by which the effects of maternal undernutrition on fetal growth are mediated. In the compact placenta of the guinea pig the exchange surface is equivalent to the peripheral labyrinth. The effect of a 40% reduction in maternal feed intake on the growth of the peripheral labyrinth was investigated in pregnant guinea pigs between gestational days 25 and 65. Fetal and placental weights were significantly reduced in the last trimester by 32% and 38% respectively (P < 0.01). Placental efficiency in early gestation was significantly impaired in restricted animals but equivalent to ad lib. fed controls by the last trimester. The volume of the peripheral labyrinth increased as a percentage of the total placental volume with gestational age. Restricted placentae tended to be composed of a smaller volume of peripheral labyrinth tissue in early gestation. It is suggested that maternal undernutrition results in an impaired or delayed expansion of the peripheral labyrinth in early gestation causing a reduction in placental efficiency. By the last trimester the weight of the peripheral labyrinth of restricted animals was reduced by 33% (P < 0.05). The weight of the peripheral labyrinth was also significantly correlated with fetal weight is limited by the size of the peripheral labyrinth in the later stages of gestation.     

Organ culture of human placental villi in hypoxic and hyperoxic conditions: a morphometric study

Previously published reports have claimed that human placental villi are capable of adapting to hypoxia by thinning of the placental barrier which normally separates the fetal from the maternal circulation. In order to examine this effect further, terminal villi from three normal mature placentas were cultured for periods of 1, 6 and 12 h at different oxygen tensions. Diffusion distance and capillary volume fraction were measured on 1 micron plastic sections on a blind basis, but no statistically significant differences were observed between the cultured sample groups and control material. It is concluded that placental villi show no adaptation to acute hypoxia when maintained in organ culture in vitro. It is possible, however, that they undergo changes in vivo, secondary to vasodilatation of the umbilical arteries and placental arterioles.     

Recent environmental toxic effect in the Polish copper mining territory on human reproduction. Part I. Response of the placenta to the chemical stress

This study examined morphochemical differences between 49 full term human placentas collected from healthy non-smoking women living in the high polluted region, i.e. the Copper Mining Territory (CMT) and the 38 control placentas (C) obtained from little polluted eastern Carpathian regions. The placentas were studied by histochemical, immunohistochemical and morphometric methods. In CMT placentas a decrease in the cytochrome c oxidase and glucose-6-phosphate activities and the immunoreactivity of glutathione S-transferase pi in the villous syncytiotrophoblast and amniotic epithelium was noted. All CMT placentas showed abundance of mineral and fibrinoid deposits and of lipid droplets. This produced a compensatory increase in the mother-fetus exchange area due to excessive proliferation of placental villi which in turn decreased the intervillous space and thus the influx of indispensable maternal blood. Lately slight signs of increase in the cytochrome c oxidase activity accompanied by a noticeable decrease in number of the thinnest (most abundant) terminal villi is observed.     

The effect of progesterone administration on the expression of metastasis tumor antigens (MTA1 and MTA3) in placentas of normal and dexamethasone-treated rats

Background

Dexamethasone (DEX) induces intrauterine growth restriction (IUGR) in pregnant rats. IUGR can occur due to apoptosis of trophoblasts, which is believed to be inhibited by progesterone (P4). A group of genes called MTAs play a role in proliferation and apoptosis. MTA1 upregulates trophoblasts proliferation and differentiation, while MTA3 downregulates proliferation and induces apoptosis. Hence, we hypothesized that during IUGR, placental MTA1 decreases and MTA3 increases and this is reversed by P4 treatment.

Methods

Pregnant Sprague–Dawley rats were divided into 4 groups based on daily intraperitoneal injections: control (C, saline), DEX (DEX, 0.2 mg/kg/day), DEX and P4 (DEX?+?P4, DEX: 0.2 mg/kg/day, P4: 5 mg/kg/day) and P4-treated (P4, 5 mg/kg/day) groups. Injections were started on 15 dg until the day of dissection (19 or 21 dg). Gene and protein expressions of MTA1 and MTA3 were studied in the labyrinth (LZ) and basal (BZ) zones using real-time PCR and Western blotting, respectively.

Results

DEX treatment induced 18% reduction in fetal body weight (p?<?0.001) and 30% reduction in placental weight (p?<?0.01). Maternal P4 level was also significantly lower in DEX treated groups (p?<?0.05). MTA1 expression was decreased in the LZ (gene, p?<?0.001) and BZ (protein p?<?0.01), while MTA3 protein expression was upregulated in the LZ with DEX treatment (p?<?0.001). These changes were reversed with P4 treatment.

Conclusion

The findings of the present study indicate that DEX induces IUGR through changing the expression of placental MTA1 and MTA3 antigens and P4 improved pregnancy outcome by preventing the changes in MTAs expression.

     

Concurrent nephrotic syndrome and acute renal failure caused by chronic lymphocytic leukemia (CLL): a case report and literature review

Background

The aim of this study was to compare histomorphometric changes and the results of immunohistochemical tests for VCAM, ICAM-1, CD4 and CD8 in normal placentas from HIV-seropositive pregnant women.

Methods

Samples of normal placentas were divided into 2 groups: healthy HIV-seronegative pregnant women (control group = C = 60) and HIV-seropositive women (experimental group = E = 57). Conventional histological sections were submitted to morphometric analysis and evaluated in terms of the immunohistochemical expression of ICAM-1, VCAM, CD4 and CD8.

Results

The villi in group E were smaller than those in group C. The median for the CD8+ T cell count was higher in group E than in group C (p = 0.03). Immunohistochemical expression of ICAM-1 was observed in 57% of the cases in group E, compared with 21% of those in group C (p = 0.001). There was no difference in VCAM expression or CD4+ cell counts between groups and no correlation between the data for antiretroviral therapy and morphometric or immunohistochemical data.

Conclusions

The morphometric data showed that placentas of HIV-seropositive pregnant women tend to have smaller villi than those of seronegative women. In addition, immunohistochemical testing for infectious agents helped to identify cases that were positive for microorganisms (6/112) that routine pathological examination had failed to detect. The anti-p24 antibody had a limited ability to detect HIV viral protein in this study (2/57). Correlation of immunohistochemical expression of CD8+ T cells and ICAM-1 with the presence of HIV in the placenta revealed that those expressions can act as biomarkers of inflammatory changes. There was no correlation between the data for antiretroviral therapy and morphometric or immunohistochemical data.     

Expression of the blood-group-related antigens Sialyl Lewis a,Sialyl Lewis x and Lewis y in term placentas of normal,preeclampsia, IUGR- and HELLP-complicated pregnancies

Lewis antigens belong to the blood group of antigens and mediate cellular adhesion through interaction with selectins. Invasive trophoblasts use an array of adhesion molecules to facilitate cell–cell and cell–extracellular matrix interactions. Here, we examined immunohistochemically the expression of Sialyl Lewis a (sLe^a), Sialyl Lewis x (sLe^x) and Lewis y (Le^y) in term placentas obtained from cases of normal, intrauterine growth retardation (IUGR), preeclamptic (PE) and hemolysis, elevated liver enzymes and low platelets syndrome (HELLP) pregnancies. We report the expression of sLe^x in third trimester extravillous trophoblasts (EVT). sLe^x was significantly decreased in IUGR and moderately decreased in PE compared to normal placentas. sLe^x was additionally found in syncytiotrophoblast, without however any significant differences in staining intensity between normal and pathological cases. sLe^a was restricted to amnion epithelium. Finally, Le^y was expressed in cytotrophoblasts and villous endothelial cells. Le^y expression was significantly upregulated in IUGR and HELLP, whereas there was a trend toward increase in PE compared to normal placentas. The present study suggests that downregulation of sLe^x in EVT might be associated with IUGR and PE. Furthermore, Le^y, which was recently described as a potent angiogenic factor, is upregulated in placental villi in conditions associated with placental malperfusion. U. Jeschke and A. Makrigiannakis have contributed equally.