Decreased Levels of Soluble Developmental Endothelial Locus-1 Are Associated with Thrombotic Microangiopathy in Pregnancy.

HELLP (Hemolysis, Elevated Liver enzymes and Low Platelets) syndrome is a life-threatening complication of pregnancy, which is often secondary to preeclampsia. To date, there is no biomarker in clinical use for the early stratification of women with preeclampsia who are under increased risk of HELLP syndrome. Herein, we show that the levels of circulating developmental endothelial locus-1 (DEL-1), which is an extracellular immunomodulatory protein, are decreased in patients with HELLP syndrome compared to preeclampsia. DEL-1 levels are also negatively correlated with the circulating levels of kidney injury molecule-1 (KIM-1), which is a biomarker for disorders associated with kidney damage. Receiver-operating characteristic curve analysis for DEL-1 levels and the DEL-1 to KIM-1 ratio demonstrates that these values could be used as a potential biomarker that distinguishes patients with HELLP syndrome and preeclampsia. Finally, we show that placental endothelial cells are a source for DEL-1, and that the expression of this protein in placenta from patients with HELLP syndrome is minimal. Taken together, this study shows that DEL-1 is downregulated in HELLP syndrome both in the circulation and at the affected placental tissue, suggesting a potential role for this protein as a biomarker, which must be further evaluated.

Role of placental inflammatory mediators and growth factors in patients with rheumatic diseases with a focus on systemic sclerosis.

OBJECTIVES: Pregnancy in SSc is burdened with an increased risk of obstetric complications. Little is known about the underlying placental alterations. This study aimed to better understand pathological changes and the role of inflammation in SSc placentas. Leucocyte infiltration, inflammatory mediators and atypical chemokine receptor 2 (ACKR2) expression in SSc placentas were compared with those in other rheumatic diseases (ORD) and healthy controls (HC). METHODS: A case-control study was conducted on eight pregnant SSc patients compared with 16 patients with ORD and 16 HC matched for gestational age. Clinical data were collected. Placentas were obtained for histopathological analysis and immunohistochemistry (CD3, CD20, CD11c, CD68, ACKR2). Samples from four SSc, eight ORD and eight HC were analysed by qPCR for ACKR2 expression and by multiplex assay for cytokines, chemokines and growth factors involved in angiogenesis and inflammation. RESULTS: The number of placental CD3, CD68 and CD11 cells was significantly higher in patients affected by rheumatic diseases (SSc+ORD) compared with HC. Hepatocyte growth factor was significantly increased in the group of rheumatic diseases patients (SSc+ORD) compared with HC, while chemokine (C-C motif) ligand 5 (CCL5) was significantly higher in SSc patients compared with ORD and HC. CCL5 levels directly correlated with the number of all local inflammatory cells and higher levels were associated with histological villitis. CONCLUSIONS: Inflammatory alterations characterize placentas from rheumatic disease patients and could predispose to obstetric complications in these subjects.

Pre-eclampsia-like syndrome induced by severe COVID-19: a prospective observational study.

OBJECTIVES: To investigate the incidence of clinical, ultrasonographic and biochemical findings related to pre-eclampsia (PE) in pregnancies with COVID-19, and to assess their accuracy to differentiate between PE and the PE-like features associated with COVID-19. DESIGN: A prospective, observational study. SETTING: Tertiary referral hospital. PARTICIPANTS: Singleton pregnancies with COVID-19 at >20+0  weeks. METHODS: Forty-two consecutive pregnancies were recruited and classified into two groups: severe and non-severe COVID-19, according to the occurrence of severe pneumonia. Uterine artery pulsatility index (UtAPI) and angiogenic factors (soluble fms-like tyrosine kinase-1/placental growth factor [sFlt-1/PlGF]) were assessed in women with suspected PE. MAIN OUTCOME MEASURES: Incidence of signs and symptoms related to PE, such as hypertension, proteinuria, thrombocytopenia, elevated liver enzymes, abnormal UtAPI and increased sFlt-1/PlGF. RESULTS: Thirty-four cases were classified as non-severe and 8 as severe COVID-19. Five (11.9%) women presented signs and symptoms of PE, all five being among the severe COVID-19 cases (62.5%). However, abnormal sFlt-1/PlGF and UtAPI could only be demonstrated in one case. One case remained pregnant after recovery from severe pneumonia and had a spontaneous resolution of the PE-like syndrome. CONCLUSIONS: Pregnant women with severe COVID-19 can develop a PE-like syndrome that might be distinguished from actual PE by sFlt-1/PlGF, LDH and UtAPI assessment. Healthcare providers should be aware of its existence and monitor pregnancies with suspected pre-eclampsia with caution. TWEETABLE ABSTRACT: This study shows that a pre-eclampsia-like syndrome could be present in some pregnancies with severe COVID-19.

Development and validation of GC-MS methods for the comprehensive analysis of amino acids in plasma and urine and applications to the HELLP syndrome and pediatric kidney transplantation: evidence of altered methylation, transamidination, and arginase activity.

We developed and validated gas chromatography-mass spectrometry (GC-MS) methods for the simultaneous measurement of amino acids and their metabolites in 10-µL aliquots of human plasma and urine. De novo synthesized trideutero-methyl esters were used as internal standards. Plasma proteins were precipitated by acidified methanol and removed by centrifugation. Supernatants and native urine were evaporated to dryness. Amino acids were first esterified using 2 M HCl in methanol and then amidated using pentafluoropropionic anhydride for electron-capture negative-ion chemical ionization. Time programmes were used for the gas chromatograph oven and the selected-ion monitoring of specific anions. The GC-MS methods were applied in clinical studies on the HELLP syndrome and pediatric kidney transplantation (KTx) focusing on L-arginine-related pathways. We found lower sarcosine (N-methylglycine) and higher asymmetric dimethylarginine (ADMA) plasma concentrations in HELLP syndrome women (n = 7) compared to healthy pregnant women (n = 5) indicating altered methylation. In plasma of pediatric KTx patients, lower guanidinoacetate and homoarginine concentrations were found in plasma but not in urine samples of patients treated with standard mycophenolate mofetil-based immunosuppression (MMF; n = 22) in comparison to matched patients treated with MMF-free immunosuppression (n = 22). On average, the global arginine bioavailability ratio was by about 40% lower in the MMF group compared to the EVR group (P = 0.004). Mycophenolate, the major pharmacologically active metabolite of MMF, is likely to inhibit the arginine:glycine amidinotransferase (AGAT), and to enhance arginase activity in leukocytes and other types of cell of MMF-treated children.

Recurrent Placental Transcriptional Profile With a Different Histological and Clinical Presentation: A Case Report.

Statistically, patients with severe pregnancy complications are at risk of recurrent complications, but it is less understood if patients present with similar or different placental pathologies in subsequent pregnancies. In this case report, we describe 2 consecutive adverse pregnancies in the same woman 4 years apart. The first pregnancy was diagnosed as early-onset preeclampsia and hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome, with placental maternal vascular malperfusion features, such as syncytial knots and accelerated villous maturity. In contrast, the second pregnancy was associated with normotensive fetal growth restriction and placental "immunological" lesions, such as massive perivillous fibrin deposition and chronic intervillositis. However, based on the expression of FLT1, LIMCH1, and TAP1 by quantitative polymerase chain reaction, the placentas from both pregnancies were found to exhibit an "immunological" transcriptional signature. This suggests that this small panel of gene expression markers may be able to predict the future reoccurrence of an immunological placental pathology despite no histological evidence within the first pregnancy. These results call for more studies looking at paired pregnancies of individuals with recurrent obstetric complications and confirm the importance of assessing matched transcriptional and histopathological placental information.

Total bile acids in the maternal and fetal compartment in relation to placental ABCG2 expression in preeclamptic pregnancies complicated by HELLP syndrome.

OBJECTIVE: To investigate total bile acid (TBA) levels in maternal (MB) and umbilical cord blood (UCB) in normotensive, preeclamptic (PE), and PE pregnancies complicated by hemolysis elevated liver enzymes and low platelets (HELLP) syndrome in the context of ABCG2 placental gene expression levels, a recently reported placental bile acid transporter. METHODS: TBA levels were determined in 83 paired MB and UCB samples of normotensive, PE and PE/HELLP pregnancies and in 22 paired arterial and venous UCB samples from uncomplicated term pregnancies. ABCG2 gene expression was measured in 104 human placentas by reverse transcriptase quantitative polymerase chain reaction. RESULTS: Overall, TBA levels in MB are higher compared to levels in UCB (p<0.0001), but this comparison looses statistical significance for the 11 PE/HELLP cases. TBA levels in maternal blood are increased in PE/HELLP compared to PE pregnancies (p=0.016). TBA levels in arterial and venous UCB from 22 normotensive pregnancies are not statistically different. ABCG2 expression is reduced in pregnancies where preeclampsia is further complicated by HELLP syndrome. ABCG2 expression in human placenta is not correlated with TBA levels in either the maternal or fetal compartment. CONCLUSION: Increased maternal TBA levels in PE/HELLP pregnancies indicate a relation between bile acids in the maternal circulation and HELLP syndrome. As overall TBA levels in maternal blood are increased compared to UCB, we conclude that the placenta partly protects the fetus from increased maternal TBA levels. This consistent difference in TBA levels between the maternal and fetal compartment is unrelated to the placental expression of ABCG2.

Trophoblast expression dynamics of the tumor suppressor gene gastrokine 2.

Gastrokines (GKNs) were originally described as stomach-specific tumor suppressor genes. Recently, we identified GKN1 in extravillous trophoblasts (EVT) of human placenta. GKN1 treatment reduced the migration of the trophoblast cell line JEG-3. GKN2 is known to inhibit the proliferation, migration and invasion of gastric cancer cells and may interact with GKN1. Recently, GKN2 was detected in the placental yolk sac of mice. We therefore aimed to further characterize placental GKN2 expression. By immunohistochemistry, healthy first-trimester placenta showed ubiquitous staining for GKN2 at its early gestational stage. At later gestational stages, a more differentiated expression pattern in EVT and villous cytotrophoblasts became evident. In healthy third-trimester placenta, only EVT retained strong GKN2 immunoreactivity. In contrast, HELLP placentas showed a tendency of increased levels of GKN2 expression with a more prominent GKN2 staining in their syncytiotrophoblast. Choriocarcinoma cell lines did not express GKN2. Besides its trophoblastic expression, we found human GKN2 in fibrotic villi, in amniotic membrane and umbilical cord. GKN2 co-localized with smooth muscle actin in villous myofibroblasts and with HLA-G and GKN1 in EVT. In the rodent placenta, GKN2 was specifically located in the spongiotrophoblast layer. Thus, the gestational age-dependent and compartment-specific expression pattern of GKN2 points to a role for placental development. The syncytial expression of GKN2 in HELLP placentas might represent a reduced state of functional differentiation of the syncytiotrophoblast. Moreover, the specific GKN2 expression in the rodent spongiotrophoblast layer (equivalent to human EVT) might suggest an important role in EVT physiology.

Effects of serum from patients with early-onset pre-eclampsia, HELLP syndrome, and antiphospholipid syndrome on fatty acid oxidation in trophoblast cells.

BACKGROUND AND AIMS: The role of metabolic disorders of long-chain fatty acid oxidation in the development of pre-eclampsia (PE), hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome and antiphospholipid syndrome (APS) is unclear. The aim of this study was to research the effects of three serum on fatty acid oxidation in trophoblast cells. METHODS: Primary human trophoblast cells and HTR8/SVneo cells were treated with serum from patients with early-onset severe PE (E-PE), E-PE with HELLP (PE-HELLP), APS, and normal pregnant women as controls (NC). Cells treated with free fatty acids (FFAs) of various lengths were used as controls. RESULTS: Triglyceride (TG) and FFA levels of the E-PE and APS groups were significantly higher than the PE-HELLP and NC groups (P < 0.05). Trophoblast cells treated with serum from the E-PE and APS groups showed obvious morphological changes and a large amount of lipid droplet deposition. Cells in the E-PE group had more severe damage of mitochondria ultrastructure, presenting with cell morphological changes, lipid droplet deposition, and mitochondria damage similar to the long-chain FFA group. FFA levels in the PE-HELLP group increased significantly compared with the NC group (P < 0.05), while TG levels did not change significantly (P > 0.05). Trophoblast cells treated with serum from the PE-HELLP group showed cellular morphology and mitochondria changes similar to the E-PE group, but had relatively less lipid droplet deposition. CONCLUSION: Serum from patients with E-PE, PE-HELLP, and APS with elevated levels of FFA had different effects on trophoblast cells, including cell morphology, lipid droplets deposition, and mitochondrial ultrastructure, suggesting disorders of lipid metabolism and fatty acid oxidation of various degrees and types. Serum from patients with E-PE led to damage similar to that of long-chain FFA in cell morphology, lipid droplet deposition and mitochondrial ultrastructure, indicating the correlation between disorders of long-chain fatty acid oxidation and the development of the disease.

Prediction of obstetrical risk using maternal serum markers and clinical risk factors.

OBJECTIVE: Abnormal maternal serum analytes (pregnancy associated plasma protein A, total human chorionic gonadotropin, alpha fetoprotein, Inhibin A, and unconjugated estriol) measured as part of aneuploidy screening programs have been associated with adverse obstetrical outcomes in euploid pregnancies. This study aimed to determine if their predictive ability could be enhanced with additional information on obstetrical history. METHOD: Forty-five thousand two hundred eighty-seven women participated in the screening program and delivered euploid singleton infants between 2010 and 2012 in British Columbia, Canada. A split-sample design was used to develop and validate prognostic models for serious perinatal events (stillbirth, preterm birth <32 weeks, or HELLP syndrome) and severe pre-eclampsia [pre-eclampsia with preterm birth <34 weeks or small for gestational age <10th percentile] using logistic regression. RESULTS: Three thousand five hundred four women (7.7%) had at least one abnormal marker using standard cut-off values. The combination of serum markers and clinical risk factors improved the ability of statistical models to predict a serious perinatal event [area under the curve (AUC) = 0.62] and severe pre-eclampsia (AUC = 0.78) compared with serum markers or clinical risk factors alone. CONCLUSIONS: While detection rates are low, the combination of maternal serum markers and obstetrical history helps to identify a small subset of women at higher risk for serious perinatal events and severe pre-eclampsia.

Placental expression of vimentin, desmin and ultrastructural changes in the villi in patients with HELLP syndrome.

OBJECTIVES: To examine placental expression of vimentin and desmin in relation to ultrastructural changes within the placental villi in cases of HELLP syndrome. STUDY DESIGN: Formaldehyde-fixed and paraffin-embedded specimens of 15 healthy pregnant and 13 Hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome, placentas were used for Harris hematoxylin staining, vimentin and desmin immunohistochemistry, and transmission electron microscopy (TEM). RESULTS: Increased of fibrinoid necrosis in vascular wall and the periphery of villi were observed in sections of the placentas with HELLP syndrome. Increased expression of vimentin in the intravillous area and increased expression of desmin on blood vessel wall, were seen in placentas of patients with HELLP syndrome when compared to placentas of healthy pregnant. CONCLUSIONS: Augmentation of intermediate filaments, desmin, vimentin may disturb normal movements of endothelial cells, and may display placental dysfunction that is unable to compensate the endothelial instability and the related hypertension in HELLP syndrome. Further studies are needed to get more definit results and also to compare HELLP syndrome with preeclampsia.

Correlation of biochemical parameters and neonatal outcome in patients with gestational hypertension.

Hypertensive disorders in pregnancy are one of the leading causes of maternal death in the world and one of the major causes of perinatal mortality. The incidence of hypertensive disorders in pregnancy is 8%-15%. Significant changes of biochemical parameters in cases of hypertensive disorders in pregnancy are increased levels of blood glucose, urea, creatinine, uric acid (hyperuricemia), transaminases, and LDH. The most increased is the level of proteinuria. Bad laboratory results and the intensification of clinical signs, with multiorgan dysfunction, are indications for termination of pregnancy.

[Interaction mechanism and influence between fatty acid oxidation in trophoblast cells and p38MAPK signal transduction pathway of severe preeclampsia].

OBJECTIVE: To investigate the effects of expression of mitochondria long-chain fatty acid oxidative enzyme (long-chain 3 hyroxyacyl CoA dehydrogenase, LCHAD) and p38 mitogen activated protein kinase (p38MAPK) signal transduction pathway in severe preeclampsia. METHODS: Serum-free trophoblast cells cultured in vitro were stimulated by early onset severe preeclampsia serum (E-PE group), late onset severe preeclampsia serum (L-PE group), HELLP syndrome serum (HELLP group), and normal pregnancy serum (NP group) respectively; each group was added DMEM/F12 medium, reduced form of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor (NADPH-I) and p38MAPK inhibitor (p38-I) to stimulate cells. Expression of mRNA and protein of LCHAD in trophoblast cells were detected by real-time PCR and western blot. RESULTS: (1)The expression of mRNA of LCHAD: the level of mRNA of LCHAD in NP+DMEM, E-PE+DMEM, E-PE+NADPH-I, E-PE+p38-I, L-PE+DMEM, L-PE+NADPH-I, L-PE+p38-I and HELLP+DMEM, HELLP+NADPH-I, HELLP+p38-I groups were 1.00 ± 0.03, 0.14 ± 0.08, 0.95 ± 0.20, 1.43 ± 1.02, 0.37 ± 0.18, 1.51 ± 0.36, 1.60 ± 0.31, 0.10 ± 0.04, 0.49 ± 0.10, 0.44 ± 0.21, respectively. The relative expressions of mRNA of LCHAD were significantly reduced in E-PE+DMEM, L-PE+DMEM and HELLP+DMEM groups compared with the NP+DMEM group (P < 0.05). Compared with the NP groups, the relative expressions of mRNA of LCHAD were significantly increased in L-PE+NADPH-I and L-PE+p38-I group (P < 0.05), while reduced in HELLP groups(P < 0.05). (2) The expression of protein of LCHAD: the relative expressions of protein of LCHAD in NP+DMEM, E-PE+DMEM, E-PE+NADPH-I, E-PE+p38-I, L-PE+DMEM, L-PE+NADPH-I, L-PE+p38-I and HELLP+ DMEM, HELLP+NADPH-I, HELLP+p38-I groups were 19.4 ± 2.2, 10.7 ± 1.1, 17.9 ± 3.3, 19.1 ± 2.9, 16.4 ± 2.3, 20.3 ± 2.3, 20.9 ± 4.3, 12.4 ± 2.3, 17.6 ± 2.6, 17.7 ± 2.0 respectively. Compared with the NP groups, the protein expressions of LCHAD were significantly remarkably reduced in E-PE+DMEM, L-PE+DMEM and HELLP groups (P < 0.05). Compared with the DMEM groups, the protein expressions of LCHAD were significantly increased in NADPH-I and p38-I groups of E-PE, L-PE and HELLP groups (P < 0.05). CONCLUSIONS: These studies demonstrate that long chain fatty acid oxidation was involved in the pathogenesis and development of preeclampsia. The expressions of gene and protein of LCHAD were remarkably affected by early onset severe preeclampsia and HELLP syndrome. NADPH-I and p38-I may allay the disorder of fatty acid oxidation. p38MAPK signal transduction pathway may contributed in this process.

Role of SOX9 and Hif-1α expression in placentas of patients with HELLP.

PURPOSE: In this study, we investigated the immunohistochemical staining of SRY-box transcription factor 9 (SOX9) and Hif-1α expression in placentas of pregnant woman with hemolysis, elevated liver enzymes and low platelets (HELLP) syndrome. METHODS: Placentas of 20 normotensive and 20 women with HELLP syndrome were processed for routine histological tissue processing. The biochemical and clinical parameters of patients were recorded. Placentas were stained with hematoxylin-eosin and SOX9 and Hif-1α immunostaining. RESULTS: Normotensive placentas showed normal histology of placenta, however placentas of HELLP syndrome showed intense thrombosis, thinning of the villi membrane and vascular dilatation. In placentas of normotensive patients, SOX9 reaction was immunohistochemically negative, however placentas of HELLP group showed SOX9 expression in decidual cells, and syncytial regions of floating villi and inflammatory cells. In placentas of normotensive patients, Hif-1α reaction was mainly negative in vessels and connective tissue cells. Placentas of HELLP group showed increased Hif-1α expression in decidual cell and especially inflammatory cells in the maternal region. CONCLUSIONS: Hif-1α and SOX9 proteins can be used as a marker to show severity of preeclampsia and regulation of cell proliferation and angiogenesis during placental development.

Role of cited-1 and caspase-6 expression in HELLP syndrome.

OBJECTIVE: In this study, we investigated the immunohistochemical staining of cited-1 and caspase-6 expression in the placentas of pregnant women with HELLP syndrome. PATIENTS AND METHODS: Placentas of 20 normotensive patients and 20 women with HELLP syndrome were processed for routine histological tissue processing. The biochemical and clinical parameters of patients were recorded. Placentas were stained with hematoxylin-eosin and cited-1 and caspase-6 immunostaining. RESULTS: Placentas of normotensive patients showed normal histology. Placentas of women with HELLP syndrome showed degenerated cells, hyalinization and vacuolization. Cited-1 expression was negative in normotensive group; however, it was increased in HELLP group, especially in decidual cells, endothelial cells and other placental cells. Caspase-6 expression was negative in placental structures of normotensive groups. However, it was intense in decidual cells, vacuolar and hyalinized areas, inflammatory cells and connective tissue cells in HELLP group. CONCLUSIONS: Cited-1 and caspase-6 are a marker in determining the severity of HELLP syndrome.

Angiotensin-1 and vimentin expression and ultrastructural examination in severe preeclampsia complicated by HELLP syndrome changes in the structure of the umbilical cord.

OBJECTIVE: The purpose of this study was to examine the histopathologic, ultrastructural and immunohistochemical changes in the umbilical cord in women diagnosed with HELLP syndrome. MATERIALS AND METHODS: Postpartum umbilical cords of 40 patients at the 35-38th week of pregnancy were included. 20 severe preeclamptic (HELLP) and 20 normal umbilical cords were used. After the follow-up of tissue parts of 10% formaldehyde solution for histopathology and immunohistochemistry, histopathological and angiopoietin-1 and vimentin antibodies were examined as immunohistochemical after routine paraffin follow-up. For electron microscope analysis, umbilical cord samples were taken into 2.5% glutaral aldehyde solution. RESULTS: In the statistical comparison, mean difference in increased diameter and additional anomaly on the ultrasound of preeclamptic patients was statistically different compared to control patients. In the HELLP group, hyperplasia and degenerative changes, pyknosis of the endothelial cell nuclei of the vessels and apoptotic changes in some regions were observed. Immunohistochemical analysis showed that endothelial cells, basal membrane and fibroblast cells in the HELLP group expressed high levels of vimentin. Angiotensin-1 expression was increased in amniotic epithelial cells, endothelial cells and some pericyte cells. CONCLUSIONS: As a result, it was observed that the signaling that started with trophoblastic invasion with the effect of hypoxia in severe preeclampsia and continued with dysfunction in endothelial cells was parallel to the increase in angiotensin and vimentin receptors. It is thought that the ultrastructural change in endothelial cells may cause disruption of the collagenized structure in Wharton gel, which supports this, and may cause adverse effects in fetal development and nutrition.

Regulation of the human endogenous retroviral Syncytin-1 and cell-cell fusion by the nuclear hormone receptors PPARγ/RXRα in placentogenesis.

Cytotrophoblast (CT) cell fusion into a syncytiotrophoblast is obligatory for placentation and mediated by the human endogenous retrovirus (HERV)-W envelope gene Syncytin-1. Abnormal placentation is associated with preeclampsia (PE), HELLP and intrauterine growth restriction (IUGR). In placentogenesis, the MAP-kinase p38α regulates PPARγ/RXRα signaling and target genes, like leptin, resistin, ABCG2, and hCG. The aim of this study was to analyze PPARγ/RXRα signaling and target gene regulation using primary CT cultures, the trophoblastic cell line BeWo and placental tissues from patients with normal and abnormal placentation. CT from four different human control placentae and BeWo cells demonstrated that Syncytin-1, other signaling members and CT cell fusions were regulated with PPARγ/RXRα activators troglitazone and 9-cis retinoic acid, via protein kinase A and p38α inhibition. Significant discordant regulations between CTs and BeWo were found. Two PPARγ/RXRα-response-elements from upstream regulatory elements and the 5'LTR of HERV-W were confirmed with DNA-protein binding assays using nuclear extracts and recombinant PPARγ/RXRα proteins. These promoter elements were validated with luciferase assays in the presence of PPARγ/RXRα modulators. Furthermore, troglitazone or 9-cis retinoic acid treatment of siRNA-PPARγ and siRNA-RXRα transfected BeWo cells proved the requirement of these proteins for Syncytin-1 regulation. Thirty primary abnormal placentae from PE, HELLP and IUGR patients compared to 10 controls showed significant deregulation of leptin RNA and protein, p38α, phospho-p38α, PPARγ, ABCG2, INSL4 and Syncytin-1. Our study characterized PPARγ/RXRα signaling in human CT and cell fusions identifying Syncytin-1 as a new target gene. Based on these results, a disturbed PPARγ/RXRα pathway could contribute to pathological human pregnancies.

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.

Placental expression of endothelial and inducible nitric oxide synthase and nitric oxide levels in patients with HELLP syndrome.

OBJECTIVE: To determine placental gene expression of endothelial and inducible nitric oxide synthases and measure nitric oxide levels in patients with hemolysis, elevated liver enzyme levels, and low platelet count syndrome. STUDY DESIGN: Preterm placentas were obtained from 15 patients with hemolysis, elevated liver enzyme levels, and low platelet count syndrome and 30 controls matched for age, parity, and gestational age. mRNA levels were evaluated by real-time polymerase chain reaction, whereas nitric oxide and peroxynitrite production was measured by a commercially available kit. RESULTS: Placental gene expression of inducible nitric oxide and endothelial nitric oxide synthases were significantly lower in the hemolysis, elevated liver enzyme levels, and low platelet count syndrome group than in controls, whereas nitric oxide and peroxynitrite production were significantly higher in hemolysis, elevated liver enzyme levels, and low platelet count syndrome compared with controls. CONCLUSION: The reduced endothelial nitric oxide and inducible nitric oxide synthases gene expression in women with hemolysis, elevated liver enzyme levels, and low platelet count syndrome may indicate extreme placental dysfunction that is unable to compensate the endothelial derangement and the related hypertension. The higher nitric oxide formation found in hemolysis, elevated liver enzyme levels, and low platelet count syndrome placentas could be explained as a counteraction to the impaired fetoplacental perfusion, typical of the syndrome.

Placental protein 13 (PP13/galectin-13) undergoes lipid raft-associated subcellular redistribution in the syncytiotrophoblast in preterm preeclampsia and HELLP syndrome.

OBJECTIVE: To investigate placental protein 13 (PP13) localization in relation to cytoskeleton and lipid rafts in preeclampsia and HELLP syndrome. STUDY DESIGN: Placental cryosections from patients with preeclampsia and HELLP, and controls were stained for PP13, actin, PLAP (lipid raft marker), and CD71 (nonraft marker). BeWo cells exposed to stress conditions were stained for PP13 and actin. Protein localizations were investigated by confocal microscopy, PP13 concentrations by ELISA. RESULTS: PP13-actin colocalization was increased in syncytiotrophoblast juxtamembrane regions in term/preterm preeclampsia and HELLP. PP13-CD71 colocalization was decreased and PP13-PLAP proximity was increased in preterm but not term preeclampsia and HELLP. PP13-release from BeWo cells was inhibited by cytoskeleton disruption, and augmented by Ca2+-influx and ischemic stress. CONCLUSION: The actin cytoskeleton, probably in connection with lipid rafts, controls trophoblastic "nonclassical" PP13 export. PP13 is released from the syncytiotrophoblast in preterm preeclampsia and HELLP, mimicked in BeWo cells by ischemic stress, suggesting PP13 is a placental alarmin.

Placental expression of a novel primate-specific splice variant of sFlt-1 is upregulated in pregnancies complicated by severe early onset pre-eclampsia.

sFlt-1 is increased in the placenta and serum of women with pre-eclampsia. A novel primate-specific splice variant has recently been discovered, but its expression in severe pre-eclampsia has yet to be reported. We investigated placental expression of the previously described variant, sFlt-1/sFlt-i13, and the novel variant, sFlt-e15a, in pregnancies complicated by severe early onset pre-eclampsia (n = 14) and HELLP (haemolysis, elevated liver enzymes and a low platelet count) syndrome (n = 8). There was significant upregulation of both variants in pre-eclampsia and HELLP syndrome compared with normotensive term (n = 35) and preterm controls (n = 8). We conclude that the novel primate-specific splice variant of sFlt-1 is highly expressed in both severe pre-eclampsia and HELLP.