Immunologic abnormality of intrahepatic cholestasis of pregnancy

Assessment of the fetal thymic-thoracic ratio in pregnant women with intrahepatic cholestasis: a prospective case-control study

OBJECTIVES

To examine the fetal thymic-thoracic ratio (TTR) in intrahepatic cholestasis of pregnancy (ICP).

METHODS

This prospective case-control study was conducted in a single tertiary center. The sample consisted of 86 pregnant women at 28-37 weeks of gestation, including 43 women with ICP and 43 healthy controls. TTR was calculated for each patient using the anterior-posterior measurements of the thymus and intrathoracic mediastinal measurements.

RESULTS

The median TTR value was found to be smaller in the ICP group compared to the control group (0.32 vs. 0.36, p<0.001). The ICP group had a greater rate of admission to the neonatal intensive care unit (NICU) (p<0.001). Univariate regression analysis revealed that lower TTR values increased the possibility of NICU admission six times (95 % confidence interval: 0.26-0.39, p=0.01). A statistically significant negative correlation was detected between TTR and the NICU requirement (r: -0.435, p=0.004). As a result of the receiver operating characteristic analysis, in predicting NICU admission, the optimal cut-off value of TTR was determined to be 0.31 with 78 % sensitivity and 67 % specificity (area under the curve=0.819; p<0.001).

CONCLUSIONS

We determined that the fetal TTR may be affected by the inflammatory process caused by the maternal-fetal immune system and increased serum bile acid levels in fetal organs in the presence of ICP. We consider that TTR can be used to predict adverse pregnancy outcomes in patients with ICP.

Immune Dysfunction Mediated by the ceRNA Regulatory Network in Human Placenta Tissue of Intrahepatic Cholestasis Pregnancy

Pregnancy-related intrahepatic cholestasis (ICP) is a serious complication with adverse perinatal outcomes of preterm labor, fetal distress, or stillbirth. As a result, it is important to investigate and identify the potential critical pathogenic mechanisms of ICP. First, we collected the placental tissues from the ICP with placental weight and fetal birth weight loss for the whole transcriptome sequencing. Then we analyzed the differentially expressed (DE) circRNAs (DEcircRNAs) by SRPBM, DElncRNAs by FRKM, DEmiRNAs by TPM, and DEmRNAs by TPM and RSEM. Based on differential expression of term pregnancy placental tissues from pregnancies impacted by ICP (n=7) as compared to gestational aged matched control tissues (n=5), the circ/lncRNA-miRNA-mRNA competitive endogenous RNA (ceRNA) regulatory networks were constructed. The ceRNA regulatory networks covered 3,714 events, including 21 DEmiRNAs, 36 DEcircRNAs, 146 DElncRNAs, and 169 DEmRNAs. According to the functional analysis, ICP complications were linked to the immune system, signal transduction, endocrine system, cell growth and death, and transport and catabolism. Further evidence suggested that the expression of immune-related genes KLRD1, BRAF, and NFATC4 might have a potential ceRNA mechanism by individual lncRNA sponging miR372-3p, miR-371a-3p, miR-7851-3p, and miR-449a to control downstream the level of TNF-α, IFN-γ, and IL-10, thereby regulating the pathophysiology of ICP. Furthermore, our results were validated by the qRT-PCR, western blotting and ELISA assays. In conclusion, this study is the first to evaluate placental ceRNA networks in pregnancies affected by ICP, showing alterations in immune regulatory networks which may impact fetal and placental growth. Overall our these data suggest that the ceRNA regulatory network may refine biomarker predictions for developing novel therapeutic approaches in ICP.

Predictive and Diagnostic Value of Serum Adipokines in Pregnant Women with Intrahepatic Cholestasis

The objective of this study was to assess the value of serum leptin, adiponectin, apelin, and ghrelin as biomarkers for the prediction and diagnosis of intra-hepatic cholestasis (ICP). This prospective study included pregnant women in the third trimester of pregnancy: 63 with ICP, 48 and 15 of whom had mild and severe disease, respectively, and 32 as controls. ICP women had increased median levels of serum leptin, adiponectin, apelin, and ghrelin compared to the controls (p < 0.05). These biomarkers meaningfully changed regarding the severity of ICP: While leptin was reduced, apelin and ghrelin were increased, and adiponectin was increased somewhat. To predict and diagnose ICP, the predictive values of serum leptin, adiponectin, and apelin need to be accepted as comparable, with moderate to high sensitivity and specificity; however, the predictive value of serum ghrelin was somewhat lower. More research is needed to clarify the potential properties of adipokines to gain acceptance as a predictive or diagnostic biomarker for ICP.

Increased serum delta neutrophil index levels are associated with intrahepatic cholestasis of pregnancy

OBJECTIVE

This study aims to compare the maternal serum delta neutrophil index (DNI) levels in intrahepatic cholestasis of pregnancy (ICP) and healthy pregnancies.

METHODS

This study consisted of a group of patients (n = 40) diagnosed with isolated ICP who gave birth in our hospital and a control group (n = 60) between December 1, 2015, and June 30, 2018. The diagnosis of ICP was made based on pruritus and elevated fasting serum bile acids and liver enzymes. Laboratory tests of both groups in the hospitalization process were retrospectively examined. Maternal and neonatal characteristics, pregnancy outcomes, and DNI values of the two groups were compared. Statistical analyses were performed using SPSS version 20.

RESULTS

Mean maternal serum DNI levels were significantly higher in women with ICP than in the control group (0.49 ± 4.8 vs -3.99 ± 3.02, p = <0.01). Receiver operating characteristic (ROC) curve analysis was used to define the DNI value where ICP can be best predicted.

CONCLUSION

DNI, a new inflammatory marker, was found to be higher in women with ICP than in normal pregnancies.

Maternal serum calprotectin level in intrahepatic cholestasis of pregnancy

AIM

This study aimed to investigate maternal serum levels of calprotectin in patients with intrahepatic cholestasis of pregnancy (ICP) and to compare these with serum calprotectin levels in healthy pregnant women.

METHODS

Ninety pregnant women (ICP group, n = 45; healthy control group, n = 45) were included in the study. The gestational age and body mass index of the participants in the two groups were similar. This prospective cross-sectional study was conducted between November 2019 and May 2020 in the perinatology department of University of Health Sciences Doctor Zekai Tahir Burak Women's Education Hospital, Ankara, Turkey. Patients were recruited from those attending the perinatology outpatient and inpatient clinics. Biochemical (alanine aminotransferase (ALT), aspartate transaminase (AST), lactate dehydrogenase (LDH), total bilirubin), fasting bile acid, hemogram, and calprotectin parameters of maternal blood were evaluated.

RESULTS

The mean fasting bile acid value in the ICP group was 30.3 ± 27.3 μmol, with severe ICP present in 11 (24.4%) patients. ALT, AST, LDH, total bilirubin, and mean platelet volume (MPV) values in the ICP group were higher and the red cell distribution width (RDW) value was lower than those in the control group (p < 0.001). The mean serum calprotectin levels in the control group and ICP group were 48.0 ± 10.4 and 765.4 ± 126.8 μg, respectively (p < 0.001). There was no significant correlation between serum fasting bile acid levels and serum calprotectin levels in the ICP group (p > 0.005).

CONCLUSION

Serum levels of calprotectin in patients with ICP were higher than those in healthy pregnant women. The serum calprotectin level may be an important diagnostic marker of ICP.

Intrahepatic Cholestasis of Pregnancy Is Associated with Reduced Nitric Oxide Synthase (iNOS) in Plasma and Placentas: A Pilot Study

Background

Intrahepatic cholestasis of pregnancy (ICP) is a condition specific to pregnancy, leading to increased fetal morbidity and mortality. Nitric oxide synthase (iNOS) may be a factor regulating the vasodilation of blood vessels, which are relevant to ischemic-hypoxic conditions. We aimed to explore the potential relationship between iNOS and ICP.

Material/Methods

A prospective, case-control study was conducted including 77 pregnant women with ICP and 80 healthy pregnant women as controls. Enzyme-linked immunosorbent assays were used to investigate maternal plasma iNOS levels. The placenta mRNA levels and cell-specific localization of iNOS were determined by quantitative polymerase chain reaction, western blotting, and immunohistochemical analysis. A multivariate linear regression model was used to identify the independent factors of serum total biliary acids (TAB) in ICP.

Results

Compared with controls, the expression of iNOS was significantly lower in maternal serum and placentas with ICP (P<0.001). Maternal plasm iNOS levels were negatively correlated with TAB (r=−0.450, P<0.001), cholyglycine (r=−0.367, P<0.001), alanine aminotransferase (r=−.359, P<0.001), and aspartate aminotransferase (r=−0.329, P<0.001). iNOS level was an indicator for ICP by multivariate linear regression analysis (β=−0.505, P<0.001). The ROC curve indicated the optimal cut-off level for iNOS was 2865.43 pg/mL (sensitivity, 85.71%; specificity, 63.75%). The ROC curve area for iNOS was 0.793 (95% CI 0.722–0.864).

Conclusions

iNOS plays an important role in poor fetoplacental vascular perfusion and adverse pregnancy outcomes. iNOS can provide complementary information in predicting the extent and severity of ICP.

The Role of Melatonin, IL-8 and IL-10 in Intrahepatic Cholestasis of Pregnancy

INTRODUCTION

Intrahepatic cholestasis of pregnancy is a pregnancy-specific liver disease that usually emerges during the third trimester of pregnancy. It is characterized by itching and elevated serum total bile acid levels, and it may lead to severe fetal complications. This study aimed to investigate the role of interleukin-8, a pro-inflammatory cytokine; interleukin-10, an anti-inflammatory cytokine; and melatonin in intrahepatic cholestasis of pregnancy.

MATERIALS AND METHODS

This prospective, case-controlled study was conducted with 51 women with intrahepatic cholestasis of pregnancy (40 mild and 11 severe cases) and 43 healthy pregnant women. Serum interleukin-8, interleukin-10, and melatonin levels were evaluated.

RESULTS

Melatonin and interleukin -10 were significantly lower in subjects with intrahepatic cholestasis of pregnancy (p=0.001; p=0.001, respectively p<0.05). Interleukin-8 levels were found to be significantly higher in the cholestasis group than control group (p=0.001, p<0.05).

CONCLUSIONS

Because interleukin-8, interleukin-10, and melatonin were found to be significantly correlated with intrahepatic cholestasis of pregnancy, we believe this finding could shed light on the etiology of the disease.

Whole-exome sequencing reveals ANO8 as a genetic risk factor for intrahepatic cholestasis of pregnancy

Background

Intrahepatic cholestasis of pregnancy (ICP) is characterized by pruritus and cholestasis in late pregnancy and results in adverse pregnancy outcomes, including preterm delivery and birth weight, which are affected by the genetic and environmental background. However, until now, the genetic architecture of ICP has remained largely unclear.

Methods

Twenty-six clinical data points were recorded for 151 Chinese ICP patients. The data generated from whole-exome sequencing (WES) using the BGISEQ-500 platform were further analyzed by Burrows-Wheeler Aligner (BWA) software, Genome Analysis Toolkit (GATK), ANNOVAR tool, etc. R packages were used to conduct t-test, Fisher’s test and receiver operating characteristic (ROC) curve analyses.

Results

We identified eighteen possible pathogenic loci associated with ICP disease in known genes, covering ABCB4, ABCB11, ATP8B1 and TJP2. The loci Lys386Gln, Gly527Gln and Trp708Ter in ABCB4, Leu589Met, Gln605Pro and Gln1194Ter in ABCB11, and Arg189Ser in TJP2 were novel discoveries. In addition, WES analysis indicated that the gene ANO8 involved in the transport of bile salts is newly identified as associated with ICP. The functional network of the ANO8 gene confirmed this finding. ANO8 contained 8 rare missense mutations that were found in eight patients among the 151 cases and were absent from 1029 controls. Out of the eight SNPs, 3 were known, and the remaining five are newly identified. These variants have a low frequency, ranging from 0.000008 to 0.00001 in the ExAC, gnomAD – Genomes and TOPMED databases. Bioinformatics analysis showed that the sites and their corresponding amino acids were both highly conserved among vertebrates. Moreover, the influences of all the mutations on protein function were predicted to be damaging by the SIFT tool. Combining clinical data, it was found that the mutation group (93.36 µmol/L) had significantly (P = 0.038) higher total bile acid (TBA) levels than the wild-type group (40.81 µmol/L).

Conclusions

To the best of our knowledge, this is the first study to employ WES technology to detect genetic loci for ICP. Our results provide new insights into the genetic basis of ICP and will benefit the final identification of the underlying mutations.

Changing trends of adverse pregnancy outcomes with maternal age in primipara with singleton birth: A join point analysis of a multicenter historical cohort study in China in 2011-2012

INTRODUCTION

Adverse pregnancy outcomes are related to two opposite maternal factors, youth and aging. However, the change in trend of specific outcomes with childbearing age is unknown. The aim of this study was to investigate the changing trend of various maternal and neonatal outcomes with maternal age from 17 to 44 years.

MATERIAL AND METHODS

Data were extracted from the medical records from 2011-2012 of 39 public hospitals of 14 cities in China. The eligibility criteria were primiparity and singleton birth. Join point regression analysis was used to estimate the percent change per year of age (PCA) to explore the trends of adverse pregnancy outcomes with regard to maternal age and to identify the join point of maternal age when the trend was changed.

RESULTS

A total of 89 171 women were eligible for analysis. There were four categories of trend styles. Continuously increasing trends were linear for placenta previa (PCA, 0.1%), placenta implantation (PCA, 0.09%) and postpartum hemorrhage (PCA, 0.22%), and nonlinear for gestational diabetes mellitus with one join point of 23 years (PCA, 0.17% and 0.71%) and cesarean section with four join points of 25, 28, 31 and 36 years (PCA, 1.39%, 0.34%, 1.51%, 3.49% and 0.94%). Continuously decreasing trends were linear for intrahepatic cholestasis (PCA, -0.02%) and nonlinear for anemia with one join point of 28 years (PCA, -0.49% and -0.04%). The bidirective trends were downward to upward for preterm birth (PCA, -2.93%, -0.36% and 0.38%), hypertension in pregnancy (PCA, -0.09%, 0.47%), low birthweight (PCA 0.51% and 0.38%), low 1-minute Apgar score (PCA, -0.28% and 0.07%), low 5-minute Apgar score at (PCA, -0.10% and 0.06%) and neonatal intensive care unit admission (PCA, -1.92%, -0.07% and 0.12%) with a nadir age of 28 years. The bidirective trend was upward to downward for macrosomia (PCA, 0.39% and -0.11%), with a peak age of 30 years.

CONCLUSIONS

The changes in the trend of specific outcomes were different with maternal age, which means that youth, aging or both could affect the outcomes.

Acute fatty liver of pregnancy and concomitant medical conditions: A review of cases at a quaternary obstetric hospital

Acute fatty liver of pregnancy is a rare complication of pregnancy that may result in fulminant hepatic failure. We present a review of all patients presenting to a quaternary obstetric hospital over a 15-year period, with particular regard to biochemical changes, results of gene testing, and pre-existing conditions. Seventeen patients with acute fatty liver of pregnancy were identified. Six patients were documented to have pre-existing gastrointestinal disease; five with inflammatory bowel disease, and one with influenza A hepatitis. Antithrombin III levels were low in this study, consistent with previously published data. There were no recurrences of acute fatty liver of pregnancy in nine subsequent pregnancies to seven mothers. The authors are not aware of any literature addressing pre-existing medical conditions which may predispose to acute fatty liver of pregnancy.

The role of metabolic disorders in the pathogenesis of intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific liver disorder which typically commences in the late second or third trimester and resolves within 48 hours after delivery. It is characterized by mild to severe pruritus, without any specific dermatologic features, elevated liver enzymes and increased serum bile acids (BA). The etiology of ICP is still not completely explicit. Pathogenesis includes a combination of hormonal and environmental factors superimposing on a genetic predisposition. During recent years increasingly ICP is recognized to be associated with an abnormal metabolic profile, including glucose intolerance and dyslipidemia, although it is considered to be secondary to maternal aberrant BA homeostasis. This article reviews the recent literature data and current concepts for ICP, with emphasis on a possibility of metabolic disorders being primary causative factors in ICP pathogenesis.

Resveratrol regulates the silent information regulator 1-nuclear factor-κB signaling pathway in intrahepatic cholestasis of pregnancy

AIM

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific liver disease characterized by raised serum bile acids and adverse fetal outcomes. In this study, we aimed to explore the molecular and biochemical mechanism of resveratrol in regulating the silent information regulator 1-nuclear factor-κB (SIRT1-NF-κB) signaling pathway and bile acid biosynthesis in ICP.

METHODS

We analyzed serum and placenta samples from 30 normal and ICP pregnancy women. Then we treated HTR-8/SVneo cells with taurocholic acid (TCA) to mimic ICP conditions before treating these cells with resveratrol, as an activator of SIRT1, and EX-57, as an inhibitor of SIRT1. We established an ICP rat model to analyze the therapeutic effect of resveratrol.

RESULTS

The expression of SIRT1 protein was higher in normal placenta tissues than in ICP, and the expression of NF-κB was lower in the normal group than in the ICP group. We found that SIRT1 was downregulated, whereas NF-κB and tuor necrosis factor-α (TNF-α) were upregulated, in syncytiotrophoblast HTR-8 cells treated with TCA. This phenomenon could be reversed by resveratrol, and these effects could be blocked by Ex-527.

CONCLUSION

These data indicate that resveratrol might protect syncytiotrophoblast against TCA-induced inflammatory injury by upregulation of SIRT1 and downregulation of NF-κB and TNF-α. Resveratrol could be a potential therapeutic target for ICP.

Expression and significance of dendritic cells and Th17/Treg in serum and placental tissues of patients with intrahepatic cholestasis of pregnancy

PURPOSE

Dendritic cells (DCs) are involved in immune system, which can also regulate the differentiation of T helper 17 (Th17) and regulatory T cells (Treg). DCs and Th17/Treg participate in preeclampsia and recurrent spontaneous abortion (RSA), but there is still lack of research in intrahepatic cholestasis of pregnancy (ICP). The aim was to evaluate the expression and significance of CD83+DCs, CD1a+DCs, interleukin-17 (IL-17) and IL-35 in serum and placental tissues of patients with ICP.

METHODS

Thirty cases of mild ICP, 25 cases of severe ICP were selected, and 30 cases of normal pregnant women were selected as control group. Enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) were used to detect the expression of CD83+DCs, CD1a+DCs, IL-17 and IL-35 in serum and placenta tissues, respectively.

RESULTS

There were more CD83+DCs, IL-17 expressed in placenta from women with ICP than in normal pregnancies, while the number of decidual CD1a+DCs, IL-35 was significantly lower in ICP than in normal pregnant women. The comparison within three groups had statistical difference (p < .05). Serum CD83+DCs and CD1a+DCs levels had no significance. IL-17 was higher in ICP, while IL-35 was lower.

CONCLUSIONS

DCs are involved in damaging the maternal-fetal immune tolerance by changing the phenotype and mature state, which may affect the differentiation of Th17/Treg to cause ICP.

New insights into diagnosis and treatment of intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific disease, characterized by maternal pruritus and abnormal serum biochemistries in the late second and third trimester of pregnancy. The symptoms and abnormal biochemistries resolve rapidly after fetal delivery. As a diagnosis of exclusion, the diagnosis of ICP is based on unexplained pruritus with other causes and impaired liver function presenting with elevated serum liver transaminases and/or bile acids. It is considered as severe ICP when bile acid ≥ 40 μmol/L during pregnancy. The pathogenesis of ICP is still unclear. Adverse perinatal outcomes associated with ICP are focused on increased risk of preterm, meconium-stained amniotic fluid, and perinatal mortality. Unpredictable fetal hypoxia may result in intrauterine fetal death, fetal distress during birth and even stillbirth, and lead to an increase of iatrogenic preterm and cesarean section. The etiology and pathogenesis of fetal stress in ICP are not yet clarified, which may be associated with impaired infrastructure and decreased stress-compensatory in human utero-placental-fetal unit, and related with vascular constriction of chorionic veins and umbilical cord due to elevated bile acids in fetal serum and amniotic fluid. The essential measures of standard treatment of ICP include: (1) monitoring and evaluation of disease, uterine contraction and fetus; (2) prevention and treatment of uterine contraction; (3) treatment with ursodeoxycholic acid (500-1500 mg/d) alone or in combination with S-adenosylmehionine (800-1000 mg/d) or rifampicin (300-1200 mg/d) to promote drainage of bile acids; (4) promotion of fetal growth and lung development; (5) treatment with vitamin K1 before delivery to prevent maternal and fetal hemorrhage; (6) and timely termination of pregnancy. Gestational weeks, fetal condition and severity of disease need to be taken into account when obstetricians decide the time of termination. Elective early delivery is still an effective measure to avoid stillbirth during prolongation of gestational weeks.

Pathogenesis of Kupffer Cells in Cholestatic Liver Injury

Kupffer cells are the resident macrophages in the liver. They are located in hepatic sinusoid, which allows them to remove foreign materials, pathogens, and apoptotic cells efficiently. Activated Kupffer cells secrete various mediators, including cytokines and chemokines, to initiate immune responses, inflammation, or recruitment of other liver cells. Bile duct ligation (BDL) surgery in rodents is often studied as an animal model of cholestatic liver disease, characterized by obstruction of bile flow. BDL mice show altered functional activities of Kupffer cells compared with sham-operated mice, including elevated cytokine secretion and impaired bacterial clearance. Various mediators produced by other liver cells can regulate Kupffer cell activation, which suggest that Kupffer cells orchestrate with other liver cells to relay inflammatory signals and to maintain liver homeostasis during BDL-induced liver injury. Blocking or depletion of Kupffer cells, an approach for the treatment of liver diseases, has shown controversial implications. Procedures in Kupffer cell research have limitations and may produce various results in Kupffer cell research. It is important, however, to reveal underlying mechanisms of activation and functions of Kupffer cells, followed by hepatic inflammation and fibrosis. This review summarizes present Kupffer cell studies in cholestatic liver injury.

Immunology of hepatic diseases during pregnancy

The mother's immune system has to adapt to pregnancy accepting the semi-allograft fetus and preventing harmful effects to the developing child. Aberrations in feto-maternal immune adaptation may result in disease of the mother, such as liver injury. Five pregnancy-associated liver disorders have been described so far, however, little is known concerning immune alterations promoting the respective disease. These liver disorders are pre-eclampsia, hemolysis, elevated liver enzymes, low platelet count (HELLP), acute fatty liver, hyperemesis gravidarum, and intrahepatic cholestasis of pregnancy. On the other hand, pre-existing autoimmune liver injury of the mother can be affected by pregnancy. This review intends to summarize current knowledge linking feto-maternal immunology and liver inflammation with a special emphasis on novel potential biomarkers.

Immunological basis in the pathogenesis of intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy poses a great risk to both maternal and fetal health. Despite extensive research, much of the pathogenesis of this disorder is unknown. The increase in bile acids observed in patients with intrahepatic cholestasis of pregnancy has been noted to cause a change in the immune system from the normally mediated TH2 response to one that is more oriented towards TH1. In this literature review, we have critically reviewed the current literature regarding the changes in the immune system and the potential effects of immunological changes in the management of the patient. The current treatment, ursodeoxycholic acid, is also discussed along with potential combination therapies and future directions for research.

Effect of the maternal-fetal interface immunoregulation on the occurrence of intrahepatic cholestasis of pregnancy

Maternal immune tolerance of the fetus is indispensable for a healthy pregnancy. Currently, the study of the immune microenvironment of the maternal-fetal interface has been a heated topic in reproductive immunology research. More and more studies show that the immune imbalance in the maternal-fetal interface plays a very important role in the incidence of intrahepatic cholestasis of pregnancy (ICP). However, the precise etiology and mechanism of immune imbalance in the occurrence of ICP is still unknown. In order to clarify the potential immunologic mechanisms of ICP, this review summarizes the recent studies of the decidual immunology microenvironment and the potential immunologic mechanisms related to the development of ICP.

Human leukocyte antigen G and miR-148a are associated with the pathogenesis of intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) occurs mainly during the third trimester of gestation and is characterized by pruritus and elevated serum bile acid levels. The pathogenesis of this disease has yet to be elucidated. The nonclassical human leukocyte antigen G (HLA-G) is a trophoblast-specific molecule and is involved in the regulation of maternal immune response at the maternal-fetal interface. MicroRNAs (miRNAs) have an important role in a number of physiological and pathological processes. However, the roles of HLA-G and miRNAs in immune response in the pathogenesis of ICP have yet to be elucidated. In the present study, the expression of HLA-G and miR-148a in the placenta of patients with ICP was investigated. The mRNA and protein expression levels of HLA-G were markedly reduced in the placenta of patients with ICP compared with the levels in healthy pregnant females, and were negatively correlated with serum total bile acid (TBA) levels. It was also observed that miR-148a levels were markedly upregulated in the placenta and peripheral blood of patients with ICP. Furthermore, the mRNA and protein expression levels of HLA-G in the placenta were negatively correlated with the miR-148 levels in the placenta, but not in the peripheral blood, while the miR-148a levels in the placenta were positively correlated with serum TBA levels. These results suggest that the downregulation of HLA-G is probably caused by the upregulation of miR-148a in the placenta, and miR-148a in the placenta may contribute to the pathogenesis of ICP via the inhibition of HLA-G expression.

Roles of PPARγ/NF-κB signaling pathway in the pathogenesis of intrahepatic cholestasis of pregnancy

Background

Intrahepatic cholestasis of pregnancy (ICP) is the most prevalent pregnancy specific liver disease. However, the pathogenesis and etiology of ICP is poorly understood.

Aim

To assess the expression of peroxisome proliferator-activated receptorγ (PPARγ) and nuclear factor kappa B (NF-κB) in placenta and HTR-8/SVneo cell, and evaluate the serum levels of cytokines, bile acids, hepatic function and lipids in control and ICP patients and the fetal outcome, in order to explore the role of PPARγ/NF-κB signaling pathway in the possible mechanism of ICP.

Methods

Clinical data of the pregnant women were collected and serum levels of cytokines, bile acids, hepatic function and lipids were measured. Expressions of PPARγ and NF-κB in placenta and HTR-8/SVneo cell were determined. The new-born information was collected to demonstrate the relationship between PPARγ/NF-κB signaling pathway and ICP.

Results

The serum levels of bile acids, hepatic function, triglycerides (TG), total cholesterol (TC), IL-6, IL-12 and TNF-α in ICP group were significantly increased (P<0.01), and serum level of IL-4 was significantly decreased (P<0.01). PPARγ and NF-κB staining were found in the membrane and cytoplasm of placental trophoblast cell. The expression of PPARγ and NF-κB were significantly higher in ICP group and taurocholate acid (TCA) treated HTR-8/SVneo cell (P<0.01). The new-born information in severe ICP group were significantly different as compared to that in control group (P<0.05), and part of information in mild ICP group were also difference to that in control group (P<0.05).

Conclusions

The higher expressions of PPARγ and NF-κB in ICP placenta and TCA treated HTR-8/SVneo cell, together with the abnormal serum levels of cytokines, might induced by the imbalance of inflammatory and immune reaction, and then disturb placental bile acid and serum lipids transportation, finally result in fatal cholestasis which probably be one of the mechanism of ICP.

Human leucocyte antigen-G: expression and function in airway allergic disease

Human leucocyte antigen-G (HLA-G) is a non-classical HLA class I molecule demonstrated originally in placental trophoblast cells. Recognition of the importance of HLA-G to the maternal immune accommodation of the semi-allogeneic fetus has led to investigations of its role in the suppression of immune responses and induction of tolerance. More recently, HLA-G has been shown to have increased expression in several immunological diseases including asthma and allergic rhinitis. The focus of this review is the potential role of HLA-G in immunological airway diseases.

Impaired fetal adrenal function in intrahepatic cholestasis of pregnancy

Background

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-associated liver disease of unknown etiology. The aim of this study was to investigate the change in maternal and fetal adrenal function in clinical and experimental ICP.

Material/Methods

The maternal and fetal serum levels of cortisol and dehydroepiandrosterone sulfate (DHEAS) were determined in 14 women with ICP and in pregnant rats with estrogen-induced intrahepatic cholestasis.

Results

In women with ICP, the fetal serum cortisol and DHEAS levels were significantly higher than those in women with normal pregnancy, after correcting the impact of gestational age at delivery. The relationship between fetal cortisol and maternal cholic acid levels was bidirectional; the fetal cortisol tended to increase in mild ICP, while it decreased in severe ICP. In pregnant rats with estrogen-induced cholestasis, the fetal cortisol level was significantly lower in the group with oxytocin injection, compared with the group without oxytocin injection (191.92±18.86 vs. 272.71±31.83 ng/ml, P<0.05). In contrast, the fetal cortisol concentration was increased after oxytocin injection in normal control rats.

Conclusions

The data indicate that fetal stress-responsive system is stimulated in mild ICP, but it is suppressed in severe ICP, which might contribute to the occurrence of unpredictable sudden fetal death. Further studies are warranted to explore the role of impaired fetal adrenal function in the pathogenesis of ICP and the clinical implications.