The Role of Annexin A1 in DNA Damage Response in Placental Cells: Impact on Gestational Diabetes Mellitus.

The functions of annexin A1 (ANXA1), which is expressed on membranes and in cytoplasmic granules, have been fully described. Nonetheless, the role of this protein in protecting against DNA damage in the nucleus is still emerging and requires further investigation. Here, we investigated the involvement of ANXA1 in the DNA damage response in placental cells. Placenta was collected from ANXA1 knockout mice (AnxA1-/-) and pregnant women with gestational diabetes mellitus (GDM). The placental morphology and ANXA1 expression, which are related to the modulation of cellular response markers in the presence of DNA damage, were analyzed. The total area of AnxA1-/- placenta was smaller due to a reduced labyrinth zone, enhanced DNA damage, and impaired base excision repair (BER) enzymes, which resulted in the induction of apoptosis in the labyrinthine and junctional layers. The placentas of pregnant women with GDM showed reduced expression of AnxA1 in the villous compartment, increased DNA damage, apoptosis, and a reduction of enzymes involved in the BER pathway. Our translational data provide valuable insights into the possible involvement of ANXA1 in the response of placental cells to oxidative DNA damage and represent an advancement in investigations into the mechanisms involved in placental biology.

Histopathologic Changes in Placental Tissue Associated With Vertical Transmission of Zika Virus.

Zika virus (ZIKV) is highly neurotropic after crossing the placenta, inducing teratogenic effects that result in delayed development and microcephaly in infants. The available evidence for vertical transmission of this infection is based on placental studies showing alterations in trophoblastic tissue. However, complete characterization of ZIKV-infected placenta and involved pathways has yet to be fully clarified. This case report of placental ZIKV infection describes morphologic and molecular changes in the placenta. Hyperplasia of placental Hofbauer cells in chorionic villi and numerous histiocyte-like cells in the decidua were observed. The decidua, fibroblasts, and chorion, as well as circulating cells in the intravascular compartment stained positive for ZIKV envelop protein. Deciduitis was present on the maternal surface of the placenta, with a prevalence of lymphocytes associated with vasculitis. A high level of uncommitted CD3 T lymphocytes were present, in addition to CD4 and CD8 cells. Elevated expression of the apoptosis inhibitor, Bcl-2, was observed in syncytiotrophoblasts. These parameters may promote the persistence of ZIKV in placental tissue and transmission to the fetus.

Endogenous annexin A1 (AnxA1) modulates early-phase gestation and offspring sex-ratio skewing.

Annexin A1 (AnxA1) is a glucocorticoid-regulated anti-inflammatory protein secreted by phagocytes and other specialised cells. In the endocrine system, AnxA1 controls secretion of steroid hormones and it is abundantly expressed in the testis, ovaries, placenta and seminal fluid, yet its potential modulation of fertility has not been described. Here, we observed that AnxA1 knockout (KO) mice delivered a higher number of pups, with a higher percentage of female offsprings. This profile was not dependent on the male features, as sperm from KO male mice did not present functional alterations, and had an equal proportion of Y and X chromosomes, comparable to wild type (WT) male mice. Furthermore, mismatched matings of male WT mice with female KO yielded a higher percentage of female pups per litter, a phenomenon which was not observed when male KO mice mated with female WT animals. Indeed, AnxA1 KO female mice displayed several differences in parameters related to gestation including (i) an arrested estrous cycle at proestrus phase; (ii) increased sites of implantation; (iii) reduced pre- and post-implantation losses; (iv) exacerbated features of the inflammatory reaction in the uterine fluid during implantation phase; and (v) enhanced plasma progesterone in the beginning of pregnancy. In summary, herein we highlight that AnxA1 pathway as a novel determinant of fundamental non-redundant regulatory functions during early pregnancy.

Hyperglycemia induces inflammatory mediators in the human chorionic villous.

This study was based on the hypothesis that IL-1ß and its central regulator, the inflammasome, may play a role in the inflammatory condition exhibited by placental tissues from mothers with different gestational hyperglycemia levels. Pregnant women were classified according to the glycemic reference as non-diabetic (n = 15), mild gestational hyperglycemia (n = 15), gestational diabetes mellitus (n = 15) and type 2 diabetes mellitus (n = 15). We investigated levels of pro-inflammatory factors in maternal plasma and placental tissues (by ELISA or immunohistochemistry) and, NFKB activity (by electrophoretic mobility shift assay) and inflammasome protein expression (by Western blot) in chorionic villous. Maternal plasma and placental levels of inflammatory factors (IL-1ß, IL-6, and MCP-1) were increased during all hyperglycemic conditions. Villous stroma cells showed strong immunoreactivity to CD68. In addition, with syncytiotrophoblast, the villous stroma cells were also stained to detect iNOS, MCP-1, TLR2, and TLR4. Although the levels of protein had fluctuated in the groups, NLRP1, NLRP3, ASC, and Caspase 1 were up-regulated in all hyperglycemic groups suggesting the inflammasome may be assembled in these pregnant women. The NFKB activity also exhibited higher levels in hyperglycemic groups, which might imply in pro-inflammatory cytokines production. In summary, increased maternal glucose levels during pregnancy changed systemic and placental inflammatory patterns, which occurred in parallel with the expression of inflammasome factors and processing and secretion of the pro-inflammatory cytokine IL-1ß. These results suggest an inflammatory condition in all gestational hyperglycemic conditions, even in hyperglycemia that is less severe than gestational or overt diabetes, likely associated with inflammasome activation and inflammatory cytokine secretion. Inflammasome activation as a possible source of inflammatory factors may be an important target to be considered while managing hyperglycemia and preventing adverse pregnancy outcomes.

Stromal Cell-Derived Factor 2: A Novel Protein that Interferes in Endoplasmic Reticulum Stress Pathway in Human Placental Cells.

Endoplasmic reticulum (ER) stress results from changes in ER homeostasis and folding of proteins. ER stress initiates cellular adaptive mechanisms to rescue cell homeostasis or, if that does not work, to elicit apoptosis. We have previously shown that mouse SDF2 is sublocalized in the ER, is ubiquitously expressed, and shows strong similarities with stromal cell-derived factor (SDF) 2L1 and SDF2-like from Arabidopsis, ER proteins involved in chaperone network and protein folding. Thus, we hypothesized that SDF2 plays a role in the ER stress and unfolded protein response. In this study, we investigated the possible role of SDF2 in the human placenta. Expression of SDF2 was present throughout gestation and was expressed by several cell types. Second-trimester cytotrophoblast cells (CTBs) in the differentiation process, monitored through chorionic gonadotropin production, showed upregulation of SDF2 protein. SDF2 expression, however, was significantly diminished in placentas from neonates small for gestational age and in hypoxic in vitro conditions (P ≤ 0.001, 2% O2), suggesting a link with cellular stress. ER stress-induced cells-CTB and BeWo-also showed SDF2 downregulation in different time points, emphasizing this relationship. SDF2 downregulation was also followed by an increase in binding immunoglobulin protein (BiP) expression, an ER protein-associated chaperone acting as a sensor for misfolded proteins and an ER stress cell survival marker. In line with this, SDF2 siRNA resulted in significant anticipation of BiP expression. Downregulation of SDF2 also interfered with C/EBP homologous protein expression, one of the highest inducible genes during ER stress. These findings suggest that SDF2 may be an important regulatory factor by which trophoblast cells can control cell survival under ER stress. In conclusion, this study identifies a novel factor with the ability to interfere with ER stress proteins, which may contribute to the understanding of ER stress associated with placental-related diseases of pregnancy.

Decorin and biglycan immunolocalization in non-villous structures of healthy and pathological human placentas.

AIMS: Decorin and biglycan are members of the small leucine-rich proteoglycan family, and constituents of both the extracellular matrix (ECM) and the cell surface. They are recognized as important factors in the control of proliferation, migration and invasion in vivo and in vitro. In this study, the localization patterns of decorin and biglycan were determined in healthy placentas and in highly invasive placental pathologies. METHODS AND RESULTS: The study included immunolocalization of decorin and biglycan in samples of first-trimester and term placentas, placenta accreta, invasive mole, and choriocarcinoma. Extravillous cytotrophoblast (EVT) cells were positive for both proteoglycans in all pathologies and in first-trimester placentas, although not in term placentas. Biglycan was immunolocalized in the ECM of all healthy and pathological placentas, whereas decorin was observed only in term placenta ECM. CONCLUSIONS: The expression of both proteoglycans was cell-specific and gestation time-dependent in healthy placentas, and was associated with invasive EVT cells in pathological placentas. In view of the biological properties of these molecules, it is possible that the biglycan pattern found here is intrinsically implicated in the invasive activity of EVT cells in both healthy and disordered placentas.

The term basal plate of the human placenta as a source of functional extravillous trophoblast cells.

BACKGROUND: Extravillous trophoblast (EVT) cells are of pivotal importance in human embryo implantation and homeostasis of the maternal fetal interface. Invasion of the endometrium by EVT contributes to placental anchorage, spiral artery remodeling, immunological defense, tolerogenic responses, and several collaborative cross talks involved in establishing and maintaining a successful pregnancy. We report here an improved protocol for the isolation of fully differentiated EVT cells from the basal plate of the human term placenta. METHODS: The basal plate was carefully dissected from the villous tissue and the amniochorion membrane prior to enzymatic digestion. Term basal EVT cells were isolated using a 30 and 60% Percoll gradient. A panel of markers and characteristics of the isolated cells were used to confirm the specificity and efficiency of the method so that their potential as an investigative tool for placental research could be ascertained. RESULTS: Isolated cells were immunoreactive for cytokeratin-7 (CK-7), placental growth factor, placental alkaline phosphatase, human leukocyte antigen G1 (HLA-G1), and α1 and α5 integrins, similarly to the EVT markers from first trimester placental villi. Around 95% of the isolated cells labeled positively for CK-7 and 82% for HLA-G1. No significant change in viability was observed during 48 h of EVT culture as indicated by propidium iodide incorporation and trypan blue test exclusion. Genes for metalloproteinases MMP-2 and MMP9 (positive regulators of trophoblast invasiveness) were expressed up to 48 h of culturing, as also the gelatinolytic activity of the isolated cells. Transforming growth factor (TGF)-beta, which inhibits proliferation, migration, and invasiveness of first-trimester EVT cells, also reduced invasion of isolated term EVT cells in transwell assays, whereas epidermal growth factor was a positive modulator. CONCLUSIONS: Term basal plate may be a viable source of functional EVT cells that is an alternative to villous explant-derived EVT cells and cell lines. Isolated term EVT cells may be particularly useful in investigation of the role of trophoblast cells in pathological gestations, in which the precise regulation and interactive ability of extravillous trophoblast has been impaired.

Peri-implantational in vivo and in vitro embryo-trophoblast development after perigestational alcohol exposure in the CD-1 mouse.

Long-term pregestational ethanol exposure induced altered fertilization and preimplantation embryogenesis. We evaluated preimplantational embryo-trophoblast differentiation, growth and invasiveness after perigestational ethanol 10% ingestion for 15 days preceding and up to day 4 (treated females [TF]: TF-D4 group) or 5 (TF-D5) of CD-1 gestation (control females [CF] with water). In TF-D4, expanded and hatched blastocyst numbers were significantly reduced (p < 0.05) versus CF-D4. Abnormal embryos and percentage of pyknotic nuclei were increased, and early blastocyst growth (nuclear number/embryo) and mitotic index was reduced (p < 0.05) versus CF-D4. On day 5 of gestation, TF-D5 presented significantly reduced total embryos and advanced embryo type 3 number versus CF-D5 (p < 0.05). During in vitro development, up to 72-hour culture, TF-D5 had reduced embryo type 1 (the least developed) and 3 percentages (p < 0.05) versus controls, whereas embryo type 2 percentage increased (p < 0.05) versus CF-D5. Embryo-trophoblast growth was studied during culture by morphometry. Embryo size ranges were classified as small, medium and large embryos. At 48-hour culture, small and medium embryos of TF had significantly increased mean area versus CF (p < 0.05), whereas large embryos had reduced mean area at 24-hour culture. Perigestational alcohol exposure up to days 4-5 induced embryo differentiation retardation, abnormal blastocyst growth and alterations of embryo-trophoblast growth and expansion during implantation, suggesting impaired regulation of trophoblast invasion and a relation with early pregnancy loss after mouse perigestational alcohol consumption.

Expression of NADPH oxidase by trophoblast cells: potential implications for the postimplanting mouse embryo.

Cytochemical localization of hydrogen peroxide-generating sites suggests NADPH (nicotinamide adenine dinucleotide 3-phosphate [reduced form]) oxidase expression at the maternal-fetal interface. To explore this possibility, we have characterized the expression and activity of the NADPH oxidase complex in trophoblast cells during the postimplantation period. Implantation sites and ectoplacental cones (EPCs) from 7.5-gestational day embryos from CD1 mice were used as a source for expression analyses of NADPH oxidase catalytic and regulatory subunits. EPCs grown in primary culture were used to investigate the production of superoxide anion through dihydroxyethidium oxidation in confocal microscopy and immunohistochemical assays. NADPH subunits Cybb (gp91phox), Cyba (p22phox), Ncf4 (p40phox), Ncf1 (p47phox), Ncf2 (p67phox), and Rac1 were expressed by trophoblast cells. The fundamental subunits of membrane CYBB and cytosolic NCF2 were markedly upregulated after phorbol-12-myristate-13-acetate (PMA) treatment, as detected by quantitative real-time PCR, Western blotting, and immunohistochemistry. Fluorescence microscopy imaging showed colocalization of cytosolic and plasma membrane NADPH oxidase subunits mainly after PMA treatment, suggesting assembly of the complex after enzyme activation. Cultured EPCs produced superoxide in a NADPH-dependent manner, associating the NADPH oxidase-mediated superoxide production with postimplantation trophoblast physiology. NADPH-oxidase cDNA subunit sequencing showed a high degree of homology between the trophoblast and neutrophil isoforms of the oxidase, emphasizing a putative role for reactive oxygen species production in phagocytic activity and innate immune responses.

Placentation in the anteaters Myrmecophaga tridactyla and Tamandua tetradactyla (Eutheria, Xenarthra).

BACKGROUND: Since Xenarthra are serious candidates for being basal to Eutheria, their characteristics, e.g. the placental system, influence perceptions of evolution. However, in the subgroup containing the anteaters, data are very limited. The present study aims to elucidate the nature of the feto-maternal interface in the anteater placenta and to interpret these data within an evolutionary context. METHODS: Placentas of two species were investigated with histology, immunohistochemistry and transmission electron microscopy. RESULTS: Remnants of the maternal vessel endothelium were absent, resulting in a fully haemochorial barrier throughout the placenta. Two structurally different parts, the villous and trabecular areas were complex and intermingled. In particular, the trabeculae which consisted of cellular, proliferative trophoblast, associated with connective tissue, were attached to the decidua. The villi contained fetal capillaries and hypertrophied mesenchymal cells that occurred near the surface near the end of gestation. The surface of the villi consisted of flat, syncytial trophoblast, interspersed with proliferative trophoblast cells. CONCLUSIONS: Based on fundamental differences between anteaters and armadillos, we inferred that placental evolution was more complex than previously thought. The haemochorial pattern of anteaters was likely an ancient condition of xenarthrans. Consequently, villous placentation may be attributed, at least in part, by convergent evolution, but was also characterized by some features that were widespread among xenarthrans.

NADPH oxidase as an important source of reactive oxygen species at the mouse maternal-fetal interface: putative biological roles.

Oxygen derivatives that comprise the large family of reactive oxygen species (ROS) are actively involved in placental biology. They are generated at the maternal-fetal interface at the level of decidual, trophoblast and mesenchymal components. In normal conditions, ROS produced in low concentrations participate in different functions as signalling molecules, regulating activation of redox-sensitive transcription factors and protein kinases involved in cell survival, proliferation and apoptosis, hence much of cell functioning. Physiological ROS generation is also associated with such defence mechanisms as phagocytosis and microbiocidal activities. In mice, particularly but not exclusively, trophoblast cells phagocytose intensively during implantation and post-implantation periods and express enzymic machinery to address a ROS-producing response to changes in the environment. The cells directly associated with ROS production are trophoblast giant cells, which mediate each and every relationship with the maternal organism. In this review, the production of ROS by the implanting mouse trophoblast is discussed, focusing on NADPH oxidase expression, regulatory mechanisms and similarities with NOX2 from phagocytes. Some of the current controversies are assessed by attempting to integrate data from studies in human trophoblast and mouse models.

Expression of angiogenic factors in placenta of stressed rats.

The aim of the present study was to analyse the influence of stress on pregnant rats, particularly in terms of maternal, placental and fetal weight, placental morphology and placental gene expression of the angiogenic factors Vegfa and Pgf and their receptors. The parameters were evaluated on gestation Day 20. Maternal, fetal and placental weights were statistically lower in stressed animals than controls, suggesting abnormalities in gestational physiology. Morphologically the placentas of rats subjected to stress were reduced in size and weight, with few glycogen cells and a significant increase in the number of apoptotic cells. Stress caused an increase in placental gene expression of Vegfa (P<0.05) and a reduction in Pgf, Flt1 and Kdr expression (P<0.05). It has been suggested that increased VEGF is associated with vasodilatation and hypotension, but in this model persistent hypertension was present. This study suggests that the limited hypotensive Vegfa response to stress-induced hypertension could result from reduced expression of Flt1/Kdr disrupting specific VEGF pathways. These findings may elucidate one of the multiple possible factors underlying how stress modulates placental physiology, and could aid the understanding of stress-induced gestational disorders.

CRIPTO-1 Is Immunolocalized in the Syncytiotrophoblast of Ampullary Pregnancies.

Introduction: Controlling the invasive activity of trophoblastic tissue has not been elucidated. In the accreta placenta, the invasion of placental tissue is directly related to the expression of CRIPTO-1 at the maternal-fetal interface. The aim of this study is to evaluate if the expression of the CRIPTO-1 is related to different degrees of trophoblast invasion into the tube wall in ampullary pregnancy. Methods: Prospective study with 21 patients with ampullary tubal pregnancy undergoing salpingectomy. Anatomopathological evaluation determined the degree of invasion of trophoblast tissues into the tubal wall and grouped the samples into invasive degrees I, II, or III. The groups were compared for tissue expression of CRIPTO-1 using the Kruskal-Wallis nonparametric test. p values lower than 0.05 were considered significant. Results: Quantitative expression of CRIPTO-1 differed in each of the three groups of trophoblast invasion in the tubal wall in ampullary pregnancies (p < 0.001). There is a difference between groups when grade I + grade II versus grade III (p < 0.001) and grade I versus grade II + grade III (p < 0.001). The tissue expression of CRIPTO-1 in ectopic trophoblasts showed that deeper invasion of the tubal wall was associated with stronger expression than in shallow invasion (p < 0.001). Discussion. In ampullary pregnancies, the depth of penetration of trophoblast tissue in the tubal wall is related to CRIPTO-1 tissue expression.

The impact of Zika virus exposure on the placental proteomic profile.

Zika virus (ZIKV) infection has caused severe unexpected clinical outcomes in neonates and adults during the recent outbreak in Latin America, particularly in Brazil. Congenital malformations associated with ZIKV have been frequently reported; nevertheless, the mechanism of vertical transmission and the involvement of placental cells remains unclear. In this study, we applied quantitative proteomics analysis in a floating explant model of chorionic villi of human placental tissues incubated with ZIKV and with ZIKV pre-adsorbed with anti-ZIKV envelope protein. Proteomic data are available via ProteomeXchange with identifier PXD025764. Altered levels of proteins were involved in cell proliferation, apoptosis, inflammatory processes, and the integrin-cytoskeleton complex. Antibody-opsonized ZIKV particles differentially modulated the pattern of protein expression in placental cells; this phenomenon may play a pivotal role in determining the course of infection and the role of mixed infections. The expression of specific proteins was also evaluated by immunoperoxidase assays. These data fill gaps in our understanding of early events after ZIKV placental exposure and help identify infection control targets.

The effect of Ipomoea carnea on maternal reproductive outcomes and fetal and postnatal development in rats.

Ipomoea carnea is a toxic plant found in Brazil and other tropical countries. The plant contains the alkaloids calystegines and swainsonine, which inhibit key cellular enzymes and cause systematic cell death. It is known that swainsonine is excreted in the amniotic fluid of dams exposed to the plant. Thus, the aim of this study was to verify whether the toxic effect of I. carnea on fetuses is due to exclusively the passage of the active principle of the plant through the placenta, or if the placentotoxic effect of swainsonine could collaborate in the adverse effects observed in the fetus. The teratogenic effects of exposure to the toxic principles of I. carnea were evaluated not only using the conventional protocol but also at later stages in the postnatal developmental period. Females were treated, from gestation day (GD) 6 until GD19, with 0.0, 1.0, 3.0 or 7.0 g/kg body weight of I. carnea dry leaves. The plant did not induce changes in reproductive performance or biochemical profile of the dams. Dams that received the highest dose of I. carnea showed cytoplasmic vacuolization in the liver, kidney and placental tissue. I. carnea promoted different lectin binding patterns in different areas of placental tissue. No fetal skeletal or visceral malformations was observed. The postnatal evaluation revealed a lower litter weight and a lower pup body weight one day after birth in the group that received the highest dose of I. carnea. Physical milestones were unaffected by the treatments. Female pups from all experimental groups exhibited a delay in achieving a negative geotaxis response. The results show that the toxic principle of I. carnea produces injury in utero in mothers and fetuses, but these deleterious effects were better demonstrated using postnatal evaluation.

Stromal Cell-Derived Factor (SDF) 2 and the Endoplasmic Reticulum Stress Response of Trophoblast Cells in Gestational Diabetes Mellitus and In vitro Hyperglycaemic Condition.

BACKGROUND AND AIM: The endoplasmic reticulum (ER) stress response and the unfolded protein response (UPR) are essential cellular mechanisms to ensure the proper functioning of ER in adverse conditions. However, activation of these pathways has also been associated with insulin resistance and cell death in pathological conditions such as diabetes mellitus. In the present study, we investigated whether stromal cell-derived factor 2 (SDF2)-an ER stress-responsive factor-is related to ER response in placental cells exposed to maternal gestational diabetes mellitus (GDM) or to a hyperglycaemic in vitro condition. OBJECTIVE: The study aimed to investigate the role of SDF2 in BeWo cells , a trophoblast cell line originating from choriocarcinoma , and in placental tissue under hyperglycaemic conditions. METHODS: Protein levels of SDF2 and UPR factors, glucose-related protein 78 (GRP78) and eukaryotic initiation factor 2 alpha (elF2 alpha) were evaluated in the placentae of pregnant women diagnosed with GDM and treated by diet-control (insulin was added when necessary). The mRNA expression of SDF2 and UPR factors CHOP and sXBP1 were assessed in cultured BeWo cells challenged with glucose and treated with or without insulin. RESULTS: SDF2 expression was increased in the placentae of GDM women treated with diet. However, its values were similar to those of normoglycemic controls when the GDM women were treated with insulin and diet. BeWo cells cultured with high glucose and insulin showed decreased SDF2 expression, while high glucose increased CHOP and sXBP1 expression, which was then significantly reverted with insulin treatment. CONCLUSION: Our findings extend the understanding of ER stress and SDF2 expression in placentae exposed to hyperglycaemia, highlighting the relevance of insulin in reducing the levels of ER stress factors in placental cells. Understanding the effect of ER stress partners such as SDF2 on signalling pathways involved in gestation, complicated by hyperglycaemia, is pivotal for basic biomedical research and may lead to new therapeutic possibilities.

Serum From Preeclamptic Women Triggers Endoplasmic Reticulum Stress Pathway and Expression of Angiogenic Factors in Trophoblast Cells.

Preeclampsia (PE) is a hypertensive disease of pregnancy-associated with placental cell death and endoplasmic reticulum (ER) stress. It is unknown whether systemic factors aggravate placental dysfunction. We investigated whether serum factors in pregnant women with PE activate ER stress and unfolded protein responses (UPRs) in placental explants and trophoblast cells lineage. We cultured placental explants from third-trimester term placentas from control non-preeclamptic (NPE) pregnant women with serum from women with PE or controls (NPE). In PE-treated explants, there was a significant increase in gene expression of GADD34, CHOP, and SDF2. At the protein level, GRP78, SDF2, p-eIF2α, and p-eIF2α/eIF2α ratio were also augmented in treated explants. Assays were also performed in HTR8/SV-neo trophoblast cell line to characterize the putative participation of trophoblast cells. In PE serum-treated protein levels of p-eIF2a and the ratio p-elF2 α/elF2α increased after 12 h of treatment, while the gene expression of GADD34, ATF4, and CHOP was greater than control. Increased expression of SDF2 was also detected after 24 h-cultured HTR8/SV-neo cells. PE serum increased sFLT1 gene expression and decreased PlGF gene expression in placental explants. Morphologically, PE serum increased the number of syncytial knots and reduced placental cell metabolism and viability. Analysis of the serum of pregnant women with PE through Raman spectroscopy showed changes in amino acids, carotenoids, lipids, and DNA/RNA, which may be associated with the induction of ER stress found in chorionic villi treated with this serum. In conclusion, this study provides evidence that the serum of pregnant women with PE may impact placental villi changing its morphology, viability, and secreted functional factors while triggers ER stress and an UPR. The differences between PE and control sera include molecules acting as inducing factors in these processes. In summary, the results obtained in our assays suggest that after the development of PE, the serum profile of pregnant women may be an additional factor that feeds a continuous imbalance of placental homeostasis. In addition, this study may expand the possibilities for understanding the pathogenesis of this disorder.

Exosome-Enriched Plasma Analysis as a Tool for the Early Detection of Hypertensive Gestations.

Hypertensive disorders of pregnancy are closely associated with prematurity, stillbirth, and maternal morbidity and mortality. The onset of hypertensive disorders of pregnancy (HDP) is generally noticed after the 20th week of gestation, limiting earlier intervention. The placenta is directly responsible for modulating local and systemic physiology by communicating using mechanisms such as the release of extracellular vesicles, especially exosomes. In this study, we postulated that an analysis of exosome-enriched maternal plasma could provide a more focused and applicable approach for diagnosing HDP earlier in pregnancy. Therefore, the peripheral blood plasma of 24 pregnant women (11 controls, 13 HDP) was collected between 20th and 24th gestational weeks and centrifuged for exosome enrichment. Exosome-enriched plasma samples were analyzed by Raman spectroscopy and by proton nuclear magnetic resonance metabolomics (1H NMR). Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to analyze the Raman data, from the spectral region of 600-1,800 cm-1, to determine its potential to discriminate between groups. Using principal component analysis, we were able to differentiate the two groups, with 89% of all variances found in the first three principal components. In patients with HDP, most significant differences in Raman bands intensity were found for sphingomyelin, acetyl CoA, methionine, DNA, RNA, phenylalanine, tryptophan, carotenoids, tyrosine, arginine, leucine, amide I and III, and phospholipids. The 1H NMR analysis showed reduced levels of D-glucose, L-proline, L-tyrosine, glycine, and anserine in HDP, while levels of 2-hydroxyvalerate, polyunsaturated fatty acids, and very-low-density lipoprotein (VLDL) were increased. 1H NMR results were able to assign an unknown sample to either the control or HDP groups at a precision of 88.3% using orthogonal partial least squares discriminant analysis and 87% using logistic regression analysis. Our results suggested that an analysis of exosome-enriched plasma could provide an initial assessment of placental function at the maternal-fetal interface and aid HDP diagnosis, prognosis, and treatment, as well as to detect novel, early biomarkers for HDP.

Spatiotemporal patterns of macrophage migration inhibitory factor (Mif) expression in the mouse placenta.

BACKGROUND: Macrophage migration inhibitory factor (MIF) has special pro-inflammatory roles, affecting the functions of macrophages and lymphocytes and counter-regulating the effects of glucocorticoids on the immune response. The conspicuous expression of MIF during human implantation and early embryonic development also suggests this factor acts in reproductive functions. The overall goal of this study was to evaluate Mif expression by trophoblast and embryo placental cells during mouse pregnancy. METHODS: Mif was immunolocalized at implantation sites on gestation days (gd) 7.5, 10.5, 13.5 and 17.5. Ectoplacental cones and fetal placentas dissected from the maternal tissues were used for Western blotting and qRT-PCR assays on the same gestation days. RESULTS: During the post-implantation period (gd7.5), trophoblast giant cells showed strong Mif reactivity. In later placentation phases (gds 10.5-17.5), Mif appeared to be concentrated in the junctional zone and trophoblast giant cells. Mif protein expression increased significantly from gd7.5 to 10.5 (p = 0.005) and from gd7.5 to 13.5 (p = 0.03), remaining at high concentration as gestation proceeded. Higher mRNA expression was found on gd10.5 and was significantly different from gd13.5 (p = 0.048) and 17.5 (p = 0.009). CONCLUSIONS: The up-regulation of Mif on gd10.5 coincides with the stage in which the placenta assumes its three-layered organization (giant cells, spongiotrophoblast and labyrinth zones), fetal blood circulation begins and population of uNK cells reaches high proportions at the maternal counter part of the placenta, suggesting that Mif may play a role in either the placentation or in the adaptation of the differentiated placenta to the uterus or still in gestational immunomodulatory responses. Moreover, it reinforces the possibility of specific activities for Mif at the maternal fetal interface.

The potential contribution of stromal cell-derived factor 2 (SDF2) in endoplasmic reticulum stress response in severe preeclampsia and labor-onset.

Endoplasmic reticulum (ER) stress occurs when the protein folding machinery in the cell is unable to cope with newly synthesized proteins, which results in an accumulation of misfolded proteins in the ER lumen. In response, the cell activates a cellular signaling pathway known as the Unfolded Protein Response (UPR), aiming to restore cellular homeostasis. Activation and exacerbation of the UPR have been described in several human pathologies, including cancer and neurological disorders, and in some gestational diseases such as preeclampsia and gestational diabetes. This review explores the participation of stromal cell-derived factor 2 (SDF2) in UPR pathways, shows new information and discusses its exacerbation regarding protein expression in severe preeclampsia and labor, both of which are associated with ER stress.