Comparative Characteristics of Sialoglycans Expression Disorders in the Placental Barrier Structures in Preeclampsia and Fetal Growth Restriction.

We compared the expression profiles of α2,3- and α2,6-sialoglycans in the glycocalyx of the placental barrier structures in early and late forms of preeclampsia and fetal growth restriction using the method of lectin histochemistry. It was found that the expression of α2,3-sialoglycans in the syncytiotrophoblast and fetal endothelium of the terminal villi of the placenta was reduced in preeclampsia in comparison with normal placenta and, on the contrary, was increased in fetal growth restriction. Significant differences were found in both clinical phenotypes of preeclampsia and fetal growth restriction. Changes in the expression pattern of α2,6-sialoglycans in the endothelium of terminal villi were more pronounced than in syncytiotrophoblast. In early and late-onset preeclampsia, a significant increase in the expression of α2,6-sialoglycans was revealed only in the fetal endothelium; in early fetal growth restriction, the expression of α2,6-sialoglycans was reduced in the endothelium, but increased in syncytiotrophoblast in late fetal growth restriction. The features of the expression of sialoglycans in structures of the placental barrier in preeclampsia and fetal growth restriction were revealed, which may indicate the pathogenetic involvement of sialoglycans in the inflammatory activation cascade in fetal growth restriction, and in preeclampsia, apparently, they are associated with impaired fetal tolerance.

Comparative Characteristics of the Expression of Fucosylated Glycans and Morphometric Parameters of Terminal Placental Villi Depending on the Severity of Preeclampsia.

We performed a comparative analysis of the expression of fucosylated glycans and morphometric characteristics of the terminal villi of the placenta, depending on the severity of preeclampsia (PE). Similar patterns of the expression of fucosylated glycans in the syncytiotrophoblast glycocalyx were revealed in the placental tissue of patients with normal pregnancy and with mild and severe PE: predominance of glycans with α1,6-fucose in the core, clustered fucose residues, and LeX glycan over α1,2-fucose-containing glycans. The expression pattern of fucosylated glycans and the composition of the endothelial glycocalyx are normally close to the expression pattern and composition of the syncytiotrophoblast glycocalyx; in case of mild and severe PE, the expression pattern of fucosylated glycans was changed uniformly, and α1,2-fucose-containing glycans significantly prevailed in the endothelial glycocalyx. According to the results of Fisher's LSD test, in patients with severe PE, the total vascular area in the villus prevailed over the indices established during physiological course of pregnancy (p=0.04) and mild PE (p=0.04). Correlation analysis revealed direct and reciprocal relationships between the morphometric characteristics of the terminal villi of the placenta and the expression of fucosylated glycans in the syncytiotrophoblast and endothelium in PE. Our results indicate a changed expression of fucosylated glycans in the glycocalyx of placental barrier structures and the morphometric parameters of villi in PE of different severity, which can affect the function of the placental barrier.

Morphometric Parameters of Placental Villi in Parturient Women with COVID-19.

We performed a comparative morphological analysis of placental villi in parturient women with mild and moderate COVID-19 infection. The area and perimeter of terminal villi, their capillaries, and syncytiotrophoblast were assessed on immunohistochemical preparations with antibodies to CD31 using an image analysis system; the parameters of fetal vascular component in the placental villi were also assessed. Changes in the studied parameters differed in parturient women with mild and moderate COVID-19 infection. The observed increase in the total perimeter with a simultaneous decrease in the total capillary area and the degree of vascularization of the placental villi in parturient women with COVID-19 indicates impairment of circulation in the fetal compartment and the development of placental hypoxia, which can be the cause of unfavorable neonatal outcomes.

The Number of Syncytial Knots and VEGF Expression in Placental Villi in Parturient Woman with COVID-19 Depends on the Disease Severity.

A comparative morphological study was carried out to analyze the number of syncytial knots and VEGF expression in placental villi in parturient women with COVID-19 categorized by the disease severity. The number of syncytial knots was assessed on specimens stained with hematoxylin and eosin. VEGF expression was determined by immunohistochemical analysis in syncytiotrophoblast and villous endothelial cells. Morphological study of the placenta tissue of parturient women with COVID-19 showed increased numbers of syncytial knots in the villi, indicating the development of preplacental hypoxia. High VEGF expression in syncytiotrophoblast and vascular endotheliocytes reflects a stereotyped response to hypoxia and can underlie the development of a preeclampsia-like syndrome. The number of syncytial knots and VEGF expression in placental villi in parturient women with COVID-19 depended on the disease severity.

Expression of fucosylated glycans in endothelial glycocalyces of placental villi at early and late fetal growth restriction.

The aim of the study was to investigate the content and distribution of fucosylated sugar residues and Lewis Y (LeY) in the endothelial glycocalyx (eGC) in placental tissue at early and late onset fetal growth restriction (FGR). Our findings demonstrated that the changes of the fucosylated glycans of type 2 (H2)/LeY in the vascular endothelium of the villi may reflect alteration of villi maturation, or adaptation to hypoxia through the change of cell proliferation potential and induction angiogenesis. Early onset FGR differs from late onset FGR by a markedly increased LeY expression, being associated with more severe pathological state.

Peculiarities of the Expression of TLR4 and Inhibitor of TLR-Cascade Tollip in the Placenta in Earlyand Late-Onset Preeclampsia.

We studied the peculiarities of the expression of TLR4 and its inhibitor Tollip in placentas obtained from women aged 23-40 years with early- and late-onset preeclampsia. Histological examination of placental tissue (hematoxylin and eosin staining) and immunohistochemical analysis with primary monoclonal antibodies to TLR4 and Tollip were performed on serial paraffin sections. It was found that the expression of TLR4 increased with increasing gestation term in both the syncytiotrophoblast and vascular endothelium of the placental villi (p<0.05). The expression of TLR4 in syncytiotrophoblast and in the endothelium in early preeclampsia was also significantly (p<0.00001) higher than in the reference group (preterm birth before 34 weeks gestation). In the vascular endothelium of placental villi, the expression of TLR4 in placentas from women with early-onset preeclampsia was higher than in late-onset preeclampsia (p=0.002), while Tollip was lower in early-onset preeclampsia than in the reference group. In preeclampsia, especially in early-onset preeclampsia, marked changes in the expression of TLR4 and Tollip in the placental tissue were detected; the severity of preeclampsia correlated with the degree of damage to the placental villi.

Change in OncomicroRNA Expression in the Placenta during Preeclampsia.

The expression of microRNA-17, microRNA-181a, and microRNA-519a in the villous tree in preeclampsia was analyzed using chromogenic in situ hybridization technique (CISH). It was found that in early-onset preeclampsia, the expression of microRNA-17 in the syncytiotrophoblast was higher (p<0.05) than in late preeclampsia, and the expression of microRNA-519a was higher (p<0.05) than in women with preterm birth at 26-31 weeks gestation. We revealed higher level of expression of microRNA-181a (p<0.05) in the cytoplasm of the syncytiotrophoblast of intermediate placental villi in the group with premature delivery in comparison with early preeclampsia. In full-term pregnancy, the expression of microRNA-181a in the vascular endothelium of placental villi was higher (p<0.02) than in women with premature deliveries. Analysis of the target genes associated with these microRNAs showed that damage to the trophoblast typical of preeclampsia, especially up to 34 weeks gestation, was accompanied by selective activation of genes participating in invasion and compensatory suppression of oncoprotective genes associated with the development of malignant neoplasms.

DAI-1 Receptor Expression in Placenta in Earlyand Late-Onset Preeclampsia.

DAI-1 receptor (DNA-dependent activator of IFN-regulatory factors; DLM-1/ZBP-1) is an innate immunity cytoplasmic receptor of the DNA-recognition receptor class of antiviral immunity. DAI-1 expression reflects the severity of the inflammatory response that plays the key role in the pathogenesis of pregnancy complications. We studied DAI-1 receptor expression in the placental villi in early- and late-onset preeclampsia. In case of early-onset preeclampsia DAI-1 staining intensity was lower (p=0.01), and in case of late preeclampsia - significantly higher (p<0.005) than in the reference groups at the corresponding gestational age. There was revealed a correlation between the decrease in DAI-1 receptor expression and the severity of disease progression.

Expression of MicroRNA-146a and MicroRNA-155 in Placental Villi in Early- and Late-Onset Preeclampsia.

We studied the expression of microRNA-146a and microRNA-155 in placental villi from 18 women (26-39 weeks of gestation) of reproductive age with early- or late-onset preeclampsia. The reference group consisted of women with physiological pregnancy and full-term gestation and with preterm birth after caesarian section on gestation week 26-31. MicroRNA-146a and microRNA-155 were detected by in situ hybridization with digoxigenin on paraffin sections. It was found that the expression of microRNA-146a in both syncytiotrophoblast of the intermediate villi and syncytial knots was lower at late-onset preeclampsia than at physiologic pregnancy of full-term period (p=0.037 and p=0.001 respectively). The expression of microRNA-155 in syncytiotrophoblast of intermediate placental villi in early-onset preeclampsia was higher than in group with preterm delivery (p=0.003). However, in syncytiotrophoblast of intermediate villi and in syncytial knots, the expression of microRNA-155 was lower at late-onset preeclampsia in comparison with full-term physiological pregnancy (p=0.005). In addition, the expression of microRNA-146a and microRNA-155 did not increase in the later terms in preeclampsia, while in the reference groups demonstrating gradual increase in the expression of these markers with increasing gestational age. Expression microRNA-146a and microRNA-155 little differed in early- and late-onset preeclampsia. These findings suggest that different variants of preeclampsia are probably characterized by common pathogenetic pathways. Damaged trophoblast cannot maintain of microRNAs synthesis at the required level, which determines the formation of a vicious circle in preeclampsia and further progression of the disease.

Ultrastructural Characteristics of Placental Telocytes.

Telocytes of placental villi were studied by electronic microscopy during physiological pregnancy. Ultrastructural features of telocytes indicating their heterogeneity and presence of at least three types of villi depending on their localization and kind were observed. All placental telocytes were characterized by small amount of organelles including mitochondria. Presence of long thin processes, which generated a branching network by contacting with each other, served as a typical feature of telocytes including telocytes of the stroma and intermediate villi. Telocytes were absent in the terminal villi.

Conditions for Collection of Placental Tissue Samples for Culturing of Multipotent Mesenchymal Stromal Cells.

Placentas from women aged 25-32 years with normal course of gestation were studied. It is essential to stick to certain methodological approaches for preparing viable multipotent mesenchymal stromal cell culture and to carry out morphological (macro and micro) evaluation of the chorionic villi, umbilical cords, and placentas. At stage I of the study, patients' histories, labor course, and examinations of the newborns should be analyzed to exclude women with genital and extragenital diseases. At stage II, it is essential to stick to special regulations and methods for collection of specimens of the cord, amnion, and placental tissue proper. Histological control of the placental structures collected for multipotent mesenchymal stromal cell culturing is obligatory.

[Morphological Features of Mesenhymal Stroma Cells of Chorionic Villi].

Background: Nowadays autologous mesenchymal placental stromal cells (MSCs) may use to treat for various diseases both of the mother and the child. Stroma of the placenta villi is appropriated origin for cell culture isolation. Aim: of the study was to evaluate the possibility for selection and use of placental tissue for mesenchymal stromal cells. Materials and methods: The present study was based on 45 placental samples of women aged 27−38 yy. who underwent surgical delivery at 36−40 weeks of gestation. 30 of these women have been enrolled in the basic group including children with congenital abnormalities (CA). The comparison group consisted of 15 patients with physiological pregnancy. We performed histological examination (with hematoxylin and eosin staining), immunohistochemical examination (with use monoclonal antibodies CD90 (1:25; Abcam, UK), СD105 (1:500; Abcam, UK), CD44 (1:25; Dako), СD73 (1:200, Abcam, UK), and electron microscopy (by microscope Philips/FEI Corporation, Eindhoven, Holland). Eclipse 80i microscope (Nikon Corporation, Japan) was used to examine the immunohistochemical reactions as a brown staining. The evaluation of the intensity of reaction was conducted by NIS-Elements Advanced Research 3.2 program (Czech Republic). Student's t-test and analysis of variance were used to compare the mean values. Differences were considered statistically significant at p<0.05. Results: Interstitial cells of the stroma of the villi with CA had fibroblastic differentiation as revealed degenerative changes of the cells. The histologic examination with hematoxylin and eosin staining revealed significant fibrosis of the stroma of the placenta villi in CA group (p<0,01). Immunohistochemical study of stem and intermediate chorionic villi revealed no significant differences in staining of CD44+, СD90+, СD73+, and CD105+ cells if compared to the control group (p>0.05). Although CD105 expression was significantly lower in the CA group (0.058±0.0049) than in the control group (0.088±0.0039) (p<0.05). However, electron microscopy detected the villi interstitial stromal cells with fibroblastic differentiation in CA group. Conclusions: Thus, it is necessary to exclude placenta with obstetrical history, somatic, and congenital pathology of the mother and the child when selecting the placental cell culture. Moreover, choosing a sample the morphological structure of the placenta should be taken into consideration. However, congenital malformations of the fetus, pathology of the mother cultivate mesenchymal stromal cells of placentas is inappropriate and should be taken advantage of the donor cells.

[Role of twin reversed arterial perfusion syndrome in the development of fetus acardius]. / Rol' sindroma obratnoi arterial'noi perfuzii bliznetsov v razvitii ploda-akardiusa.

Monochorionic multiple pregnancy has a higher risk for obstetric complications, including those due to the development of twin-to-twin transfusion syndrome and reversed arterial perfusion syndrome (TRAP sequence). The latter occurs in 0.1% of all monochorionic pregnancies. The basis for TRAP sequence is a relationship between arterial and venous anastomoses from the appropriate placental areas, causing a recipient fetus to develop at the expense of a donor fetus. The presence of abnormal anastomoses is considered to be a main cause of acardia. The prognosis for a donor fetus is also unfavorable: the mortality rates in the absence of intrauterine correction are as high as 55%.

Differences of glycocalyx composition in the structural elements of placenta in preeclampsia.

INTRODUCTION: Glycans expressed in the fetal-maternal interface were shown to exert immunomodulating effects and to mediate interactions between the cells. The aim of this study was to investigate alterations in the structure of carbohydrate chains of glycocalyx in placental tissue in pregnancies complicated with preeclampsia (PE). METHODS: A histochemical analysis of placental tissues was performed with a panel of biotinylated lectins. We analyzed placental tissues in women who had severe or moderate PE and compared them to placentas from women with normal pregnancies. RESULTS: There was decreased content of terminal residues of α(2,6)-linked sialic acid (as stained by SNA lectin) in the carbohydrate chains of glycocalyx of the endothelium of placental terminal villi in patients with moderate preeclampsia. The composition of the glycocalyx of syncytiotrophoblast in patients of this group did not differ from the control group. Amount of the glycans with terminal ß-Gal- (ECL) and α-mannosyl residues (ConA) in the syncytiotrophoblast and capillary endothelium of the placenta was significantly higher in the group with severe PE compared to the control group. The increased content of sialoglycans with α(2,6)-linked sialic acids residues were discovered in the syncytium, and the decreased content of α(2,3)-linked sialic acids residues - in the endothelium of terminal villi in preeclampsia. DISCUSSION: The most prominent alteration of the glycocalyx composition was found in the placentas of women with severe preeclampsia. It is likely that the modified glycome of syncytiotrophoblast and capillary endothelium may play an important role in pathogenesis of preeclampsia.

Specific Features of TLR4 Expression in Structural Elements of Placenta in Patients with Preeclampsia.

We studied the expression of TLR4 (Toll-like receptor 4) in the syncytiotrophoblast and vascular endothelial cells of terminal and stem placental villi in severe preeclampsia and normal pregnancy. In women of both groups, the expression of TLR4 was higher in the syncytiotrophoblast that in placental endothelial cells. In patients with severe preeclampsia, TLR4 expression in endothelial cells of terminal villi was 1.3-fold lower than in normal pregnancy. Lower TLR4 expression in the terminal villi endothelium in preeclampsia can underlie impaired recognition of damaging molecules with subsequent development of endothelial dysfunction and changes in immunological tolerance.

Expression of insulin-like growth factors in the placenta in preeclampsia.

Comparative morphological study of the placentas in women with preeclampsia and small-for-date fetuses was carried out. Expression of insulin-like growth factor-1 (IGF-1), insulin-like growth factor-2 (IGF-2), and insulin-like growth factor binding protein-3 (IGFBP-3) was detected by immunohistochemical methods. Low expression of IGF-1 and high expression of IGF-2 and IGFBP-3 in the placental tissue depending on preeclampsia severity were detected. The most pronounced changes were found in preeclampsia associated with small-for-date fetuses.

The expression of matrix metalloproteinases in placental tissue depends on the severity of undifferentiated connective tissue dysplasia.

Immunohistochemical study of MMP-2 and MMP-9 expression in placental tissue of pregnant patients with undifferentiated connective tissue dysplasia of different severity showed that more severe condition was associated with higher expression of these MMP, this underlying the development of pregnancy and labor complications. The most pronounced elevation of the studied MMP levels was found in the basal plate decidual cells in women with undifferentiated connective tissue dysplasia of more than 18 score.

Morphometric characteristics of terminal villi of the placenta in pre-eclampsia.

Comparative morphological study of the placentas from women suffering from pre-eclampsia was carried out. Morphometric studies of histological preparations showed shrinkage and low vascularization of the placental terminal villi determining the development of hypoxia.

Effect of prenatal lead exposure on superoxide dismutase activity in the brain and liver of rat fetuses.

Prenatal lead exposure had a damaging effect on Cu/Zn superoxide dismutase activity in the brain and liver of rat fetuses (20 days of gestation). The decrease in Cu/Zn superoxide dismutase activity in the brain and liver of treated fetuses reflects activation of free radical processes and impairment of the antioxidant defense system during prenatal lead exposure.

[The antioxidative defense system in the liver of rat fetuses upon antenatal exposure to lead]. / Sostoianie sistemy antioksidantnoi zashchity v pecheni potomstva krys pri antenatal'nom vozdeistvii svintsa.

The activity of Zn, Cu-containing superoxide dismutase was studied in the liver of 20-day old fetuses of female rats exposed to different concentrations of lead in different periods and during pregnancy. There were significant changes in the enzyme activity depended on a used dose of lead and on the duration of exposure to this compound. Activation of free radical processes and impairment of the antioxidative defense system are likely to be one of the basic mechanisms responsible for hepatic damage during prolonged antenatal lead intoxication.