Fetal outcomes in pregnancies complicated by intrahepatic cholestasis of pregnancy in a Northern California cohort

Bile acids evoke placental inflammation by activating Gpbar1/NF-κB pathway in intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is a cholestatic disorder with potentially deleterious consequences for fetuses. Although a clear correlation between the elevated levels of maternal serum bile acids and deficient fetal outcome has been established in clinical practice, the underlying mechanisms remain elusive. Herein, we report that bile acids induce NF-κB pathway activation via G protein-coupled bile acid receptor 1 (Gpbar1), with consequent upregulation of inflammatory genes in trophoblasts, leading to aberrant leukocyte infiltration and inflammation in placenta. Ursodeoxycholic acid (UDCA), a drug used clinically to treat ICP, competes with other bile acids for binding with Gpbar1 and thus inhibits bile acid-induced inflammatory response in trophoblasts and improves fetal survival in pregnant rats with obstructive cholestasis. Notably, inhibition of NF-κB by andrographolide is more effective than UDCA in benefiting placentas and fetuses. Thus, anti-inflammation therapy targeting Gpbar1/NF-κB pathway could be effective in suppressing bile acid-induced inflammation and alleviating ICP-associated fetal disorders.

Management of intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is the most common liver disease during pregnancy, characterized by otherwise unexplained pruritus in late second and third trimester of pregnancy and elevated bile acids and/or transaminases. ICP is associated with an increased risk of adverse perinatal outcomes for the fetus and the later development of hepatobiliary disease for the mother. Bile acids should be monitored throughout pregnancy since fetal risk is increased at serum bile acids >40 µmol/l. Management of ICP consists of treatment with ursodeoxycholic acid, which reduces pruritus. Early elective delivery is common practice but should be performed on an individualized basis as long as strong evidence supporting this practice is lacking. Mothers should be followed-up for normalization of liver function tests 6-12 weeks after delivery. Future research in large-scale studies is needed to address the impact of ursodeoxycholic acid and early elective delivery on fetal outcome.

New Insights on Intrahepatic Cholestasis of Pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is characterized by maternal pruritus, and elevated serum transaminases and bile acids. Genetic defects in at least 6 canalicular transporters have been found. Association studies stress the variability of genotypes, different penetrance, and influence of environmental factors. Serum autotaxin is a sensitive, specific, and robust diagnostic marker. Elevated maternal bile acids correlate with fetal complications. Long-term sequelae for mothers include the gallstone risk and chronic liver disease. There is an association between ICP and hepatitis C. Current treatment is ursodeoxycholic acid, owing to benefits on pruritus, liver function, safety, and decreased rates of adverse effects.

Predictors of adverse neonatal outcomes in intrahepatic cholestasis of pregnancy

OBJECTIVE

We sought to determine predictors of adverse neonatal outcomes in women with intrahepatic cholestasis of pregnancy (ICP).

STUDY DESIGN

This study was a multicenter retrospective cohort study of all women diagnosed with ICP across 5 hospital facilities from January 2009 through December 2014. Obstetric and neonatal complications were evaluated according to total bile acid (TBA) level. Multivariable logistic regression models were developed to evaluate predictors of composite neonatal outcome (neonatal intensive care unit admission, hypoglycemia, hyperbilirubinemia, respiratory distress syndrome, transient tachypnea of the newborn, mechanical ventilation use, oxygen by nasal cannula, pneumonia, and stillbirth). Predictors including TBA level, hepatic transaminase level, gestational age at diagnosis, underlying liver disease, and use of ursodeoxycholic acid were evaluated.

RESULTS

Of 233 women with ICP, 152 women had TBA levels 10-39.9 μmol/L, 55 had TBA 40-99.9 μmol/L, and 26 had TBA ≥100 μmol/L. There was no difference in maternal age, ethnicity, or prepregnancy body mass index according to TBA level. Increasing TBA level was associated with higher hepatic transaminase and total bilirubin level (P < .05). TBA levels ≥100 μmol/L were associated with increased risk of stillbirth (P < .01). Increasing TBA level was also associated with earlier gestational age at diagnosis (P < .01) and ursodeoxycholic acid use (P = .02). After adjusting for confounders, no predictors were associated with composite neonatal morbidity. TBA 40-99.9 μmol/L and TBA ≥100 μmol/L were associated with increased risk of meconium-stained amniotic fluid (adjusted odds ratio, 3.55; 95% confidence interval, 1.45-8.68 and adjusted odds ratio, 4.55; 95% confidence interval, 1.47-14.08, respectively).

CONCLUSION

In women with ICP, TBA level ≥100 μmol/L was associated with increased risk of stillbirth. TBA ≥40 μmol/L was associated with increased risk of meconium-stained amniotic fluid.

Maternal bile acid transporter deficiency promotes neonatal demise

Intrahepatic cholestasis of pregnancy (ICP) is associated with adverse neonatal survival and is estimated to impact between 0.4 and 5% of pregnancies worldwide. Here we show that maternal cholestasis (due to Abcb11 deficiency) produces neonatal death among all offspring within 24 h of birth due to atelectasis-producing pulmonary hypoxia, which recapitulates the neonatal respiratory distress of human ICP. Neonates of Abcb11-deficient mothers have elevated pulmonary bile acids and altered pulmonary surfactant structure. Maternal absence of Nr1i2 superimposed on Abcb11 deficiency strongly reduces maternal serum bile acid concentrations and increases neonatal survival. We identify pulmonary bile acids as a key factor in the disruption of the structure of pulmonary surfactant in neonates of ICP. These findings have important implications for neonatal respiratory failure, especially when maternal bile acids are elevated during pregnancy, and highlight potential pathways and targets amenable to therapeutic intervention to ameliorate this condition.

Intrahepatic Cholestasis of Pregnancy (ICP) in U.S. Latinas and Chileans: Clinical features, Ancestry Analysis, and Admixture Mapping

In the Americas, women with Indigenous American ancestry are at increased risk of intrahepatic cholestasis of pregnancy (ICP), relative to women of other ethnicities. We hypothesized that ancestry-related genetic factors contribute to this increased risk. We collected clinical and laboratory data, and performed biochemical assays on samples from U.S. Latinas and Chilean women, with and without ICP. The study sample included 198 women with ICP (90 from California, U.S., and 108 from Chile) and 174 pregnant control women (69 from California, U.S., and 105 from Chile). SNP genotyping was performed using Affymetrix arrays. We compared overall genetic ancestry between cases and controls, and used a genome-wide admixture mapping approach to screen for ICP susceptibility loci. We identified commonalities and differences in features of ICP between the 2 countries and determined that cases had a greater proportion of Indigenous American ancestry than did controls (p = 0.034). We performed admixture mapping, taking country of origin into account, and identified one locus for which Native American ancestry was associated with increased risk of ICP at a genome-wide level of significance (P = 3.1 x 10(-5), Pcorrected = 0.035). This locus has an odds ratio of 4.48 (95% CI: 2.21-9.06) for 2 versus zero Indigenous American chromosomes. This locus lies on chromosome 2, with a 10 Mb 95% confidence interval which does not contain any previously identified hereditary 'cholestasis genes.' Our results indicate that genetic factors contribute to the risk of developing ICP in the Americas, and support the utility of clinical and genetic studies of ethnically mixed populations for increasing our understanding of ICP.

The impact of total bile acid levels on fetal cardiac function in intrahepatic cholestasis of pregnancy using fetal echocardiography: a tissue Doppler imaging study

AIM

The aim of this study was to assess total bile acid (TBA) levels and its impact on systolic and diastolic functions in fetuses of mothers with intrahepatic cholestasis of pregnancy (ICP) using tissue Doppler imaging (TDI), and to explore the correlation between TBA levels and fetal cardiac function.

SUBJECTS AND METHODS

The study employed 98 pregnant women with ICP who were divided into two groups according to their bile acid levels. Fifty pregnant women without ICP represented the control group.

RESULTS

Significant differences in the myocardial tissue velocities of both mitral and tricuspid valves were found between the fetuses of mothers with ICP and TBA levels of <40 mmol/L and the control group, versus fetuses of mothers with ICP and TBA levels >40 mmol/L. There was a significant increase in neonatal respiratory distress, meconium staining and neonatal TBAs in group II compared to the control group and group I. There was a correlation between maternal TBA levels and preterm delivery, APGAR scores and neonatal TBA levels at birth. There was also a positive correlation between maternal TBA and fetal myocardial tissue velocities of both mitral and tricuspid, and fetal diastolic myocardial tissue Doppler velocities.

CONCLUSION

ICP is a very serious condition especially when maternal TBA levels are >40 mmol/L. Fetal echocardiography with tissue Doppler is a useful tool for fetal assessment in patients with ICP. It could be an indication of induction of labor in cases of ICP and bile acid levels ≥40 mol/L. Neonatal echocardiography is mandatory for follow-up and management of these neonates.

The risk of infant and fetal death by each additional week of expectant management in intrahepatic cholestasis of pregnancy by gestational age

OBJECTIVE

The objective of the study was to characterize the risk of infant and fetal death by each additional week of expectant management vs immediate delivery in pregnancies complicated by cholestasis.

STUDY DESIGN

This was a retrospective cohort study of 1,604,386 singleton, nonanomalous pregnancies of women between 34 and 40 weeks' gestation with and without intrahepatic cholestasis of pregnancy (ICP) in the state of California during the years of 2005-2008. International Classification of Diseases, 9th version, codes and linked hospital discharge and vital statistics data were utilized. For each week of gestation, the following outcomes were assessed: the risk of stillbirth, the risk of delivery (represented by the risk of infant death at a given week of gestation), and the composite risk of expectant management for 1 additional week. Composite risk combines the risk of stillbirth at this gestational age week plus the risk of infant death if delivered at the subsequent week of gestation.

RESULTS

Among women with ICP, the mortality risk of delivery is lower than the risk of expectant management at 36 weeks' gestation (4.7 vs 19.2 per 10,000). The risk of expectant management remains higher than delivery and continues to rise by week of gestation beyond 36 weeks. The risk of expectant management in women with ICP reaches a nadir at 35 weeks (9.1 per 10,000; 95% confidence interval, 1.4-16.9) and rises at 36 weeks (19.2 per 10,000; 95% confidence interval, 7.6-30.8).

CONCLUSION

Among women with ICP, delivery at 36 weeks' gestation would reduce the perinatal mortality risk as compared with expectant management. For later diagnoses, this would also be true at gestational ages beyond 36 weeks. Timing of delivery must take into account both the reduction in stillbirth risk balanced with the morbidities associated with preterm delivery.

Autotaxin activity has a high accuracy to diagnose intrahepatic cholestasis of pregnancy

BACKGROUND & AIMS

Intrahepatic cholestasis of pregnancy (ICP) is defined by pruritus, elevated total fasting serum bile salts (TBS) and transaminases, and an increased risk of adverse fetal outcome. An accurate diagnostic marker is needed. Increased serum autotaxin correlates with cholestasis-associated pruritus. We aimed at unraveling the diagnostic accuracy of autotaxin in ICP.

METHODS

Serum samples and placental tissue were collected from 44 women with uncomplicated pregnancies and 105 with pruritus and/or elevated serum transaminases. Autotaxin serum levels were quantified enzymatically and by Western blotting, autotaxin gene expression by quantitative PCR.

RESULTS

Serum autotaxin was increased in ICP (mean ± SD: 43.5 ± 18.2 nmol ml(-1)min(-1), n=55, p<0.0001) compared to other pruritic disorders of pregnancy (16.8 ± 6.7 nmol ml(-1)min(-1), n=33), pre-eclampsia complicated by HELLP-syndrome (16.8 ± 8.9 nmol ml(-1)min(-1), n=17), and pregnant controls (19.6 ± 5.7 nmol ml(-1)min(-1), n=44). Longitudinal analysis during pregnancy revealed a marked rise in serum autotaxin with onset of ICP-related pruritus. Serum autotaxin was increased in women taking oral contraceptives. Increased serum autotaxin during ICP was not associated with increased autotaxin mRNA in placenta. With a cut-off value of 27.0 nmol ml(-1)min(-1), autotaxin had an excellent sensitivity and specificity in distinguishing ICP from other pruritic disorders or pre-eclampsia/HELLP-syndrome. Serum autotaxin displayed no circadian rhythm and was not influenced by food intake.

CONCLUSIONS

Increased serum autotaxin activity represents a highly sensitive, specific and robust diagnostic marker of ICP, distinguishing ICP from other pruritic disorders of pregnancy and pregnancy-related liver diseases. Pregnancy and oral contraception increase serum autotaxin to a much lesser extent than ICP.

Agonist of farnesoid X receptor protects against bile acid induced damage and oxidative stress in mouse placenta--a study on maternal cholestasis model

INTRODUCTION

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific disorder, which is characterized by raised serum bile acid level and potential adverse fetal outcome. Farnesoid X receptor (FXR), also known as a bile acid receptor, was found to be expressed in placenta with low level. Whether activation of FXR by specific agonists could regulate the pathogenesis of ICP is still unclear.

METHODS

A model of maternal cholestasis was induced by administration of 17α-ethynylestradiol (E2) in pregnant mice for 6 days. We explored the regulatory effect of WAY-362450 (W450), a highly selective and potent FXR agonist on placenta.

RESULTS

In this study, we demonstrated that administration of E2 increased bile acid levels in mouse serum, liver and amniotic fluid. Bile acid levels were significantly decreased after W450 treatment. W450 protected against the impairment of placentas induced by E2, including severe intracellular edema and apoptosis of trophoblasts. Moreover, W450 significantly induced the expressions of FXR target bile acid transport gene ATP-binding cassette, sub-family B (MDR/TAP), member 11 (Abcb11;Bsep) in placenta. W450 could also attenuate placental oxidative stress and increase the expressions of antioxidant enzymes Prdx1 and Prdx3.

DISCUSSION AND CONCLUSION

In conclusion, our data demonstrated that FXR agonist W450 modulated bile acid balance and protected against placental oxidative stress. Thus, our results support that potent FXR agonists might represent promising drugs for the treatment of ICP.

Estrogen and Estrogen Receptor-α-Mediated Transrepression of Bile Salt Export Pump

Among diseases unique to pregnancy, intrahepatic cholestasis of pregnancy is the most prevalent disorder with elevated serum bile acid levels. We have previously shown that estrogen 17β-estradiol (E2) transrepresses bile salt export pump (BSEP) through an interaction between estrogen receptor (ER)-α and farnesoid X receptor (FXR) and transrepression of BSEP by E2/ERα is an etiological contributing factor to intrahepatic cholestasis of pregnancy. Currently the mechanistic insights into such transrepression are not fully understood. In this study, the dynamics of coregulator recruitment to BSEP promoter after FXR activation and E2 treatment were established with quantitative chromatin immunoprecipitation assays. Coactivator peroxisome proliferator-activated receptor-γ coactivator-1 was predominantly recruited to the BSEP promoter upon FXR activation, and its recruitment was decreased by E2 treatment. Meanwhile, recruitment of nuclear receptor corepressor was markedly increased upon E2 treatment. Functional evaluation of ERα and ERβ chimeras revealed that domains AC of ERα are the determinants for ERα-specific transrepression on BSEP. Further studies with various truncated ERα proteins identified the domains in ERα responsible for ligand-dependent and ligand-independent transrepression. Truncated ERα-AD exhibited potent ligand-independent transrepressive activity, whereas ERα-CF was fully capable of transrepressing BSEP ligand dependently in vitro in Huh 7 cells and in vivo in mice. Both ERα-AD and ERα-CF proteins were associated with FXR in the coimmunoprecipitation assays. In conclusion, E2 repressed BSEP expression through diminishing peroxisome proliferator-activated receptor-γ coactivator-1 recruitment with a concurrent increase in nuclear receptor corepressor recruitment to the BSEP promoter. Domains AD and CF in ERα mediated ligand-independent and ligand-dependent transrepression on BSEP, respectively, through interacting with FXR.

Intrahepatic cholestasis of pregnancy: maternal and fetal outcomes associated with elevated bile acid levels

OBJECTIVE

The primary aim of this study was to investigate the correlation between pregnancy outcome and bile acid (BA) levels in pregnancies that were affected by intrahepatic cholestasis of pregnancy (ICP). In addition, correlations between maternal and fetal BA levels were explored.

STUDY DESIGN

We conducted a retrospective study that included women with pruritus and BA levels ≥10 μmol/L between January 2005 and August 2012 in 3 large hospitals in the Netherlands. The study group was divided in mild (10-39 μmol/L), moderate (40-99 μmol/L), and severe (≥100 μmol/L) ICP. Main outcome measures were spontaneous preterm birth, meconium-stained amniotic fluid, asphyxia, and perinatal death. Univariate and multivariate logistic regression analysis was used to study associations between BA levels and adverse outcome.

RESULTS

A total of 215 women were included. Gestational age at diagnosis and gestational age at delivery were significantly lower in the severe, as compared with the mild, ICP group (P < .001). Spontaneous preterm birth (19.0%), meconium-stained fluid (47.6%), and perinatal death (9.5%) occurred significantly more often in cases with severe ICP. Higher BA levels were associated significantly with spontaneous preterm birth (adjusted odds ratio [aOR], 1.15; 95% confidence interval [CI], 1.03-1.28), meconium-stained amniotic fluid (aOR, 1.15; 95% CI, 1.06-1.25), and perinatal death (aOR, 1.26; 95% CI, 1.01-1.57). Maternal BA levels at diagnosis and at delivery were correlated positively with umbilical cord blood BA levels (P = .006 and .012, respectively).

CONCLUSION

Severe ICP is associated with adverse pregnancy outcome. Levels of BA correlate between mother and fetus.

Transcriptional dynamics of bile salt export pump during pregnancy: mechanisms and implications in intrahepatic cholestasis of pregnancy

Bile salt export pump (BSEP) is responsible for biliary secretion of bile acids, a rate-limiting step in the enterohepatic circulation of bile acids and transactivated by nuclear receptor farnesoid X receptor (FXR). Intrahepatic cholestasis of pregnancy (ICP) is the most prevalent disorder among diseases unique to pregnancy and primarily occurs in the third trimester of pregnancy, with a hallmark of elevated serum bile acids. Currently, the transcriptional regulation of BSEP during pregnancy and its underlying mechanisms and involvement in ICP are not fully understood. In this study the dynamics of BSEP transcription in vivo in the same group of pregnant mice before, during, and after gestation were established with an in vivo imaging system (IVIS). BSEP transcription was markedly repressed in the later stages of pregnancy and immediately recovered after parturition, resembling the clinical course of ICP in human. The transcriptional dynamics of BSEP was inversely correlated with serum 17β-estradiol (E2) levels before, during, and after gestation. Further studies showed that E2 repressed BSEP expression in human primary hepatocytes, Huh 7 cells, and in vivo in mice. Such transrepression of BSEP by E2 in vitro and in vivo required estrogen receptor α (ERα). Mechanistic studies with chromatin immunoprecipitation (ChIP), protein coimmunoprecipitation (Co-IP), and bimolecular fluorescence complementation (BiFC) assays demonstrated that ERα directly interacted with FXR in living cells and in vivo in mice.

CONCLUSION

BSEP expression was repressed by E2 in the late stages of pregnancy through a nonclassical E2/ERα transrepressive pathway, directly interacting with FXR. E2-mediated repression of BSEP expression represents an etiological contributing factor to ICP and therapies targeting the ERα/FXR interaction may be developed for prevention and treatment of ICP.

Pregnancy outcomes and prognostic factors in patients with intrahepatic cholestasis of pregnancy

The aim of this study was to describe maternal and fetal characteristics associated with intrahepatic cholestasis of pregnancy (ICP) and to determine clinical and biochemical predictors of fetal complications. A total of 89 singleton pregnancies with ICP were analysed, retrospectively. All data concerning laboratory results, symptom onset time, treatment response, delivery time and infant information were recorded in the study protocol. The mean gestational age at diagnosis was 32.6 ± 3.4 weeks; mean time of delivery was 36.8 ± 1.9 weeks. Binary logistic regression revealed that gestational age at diagnosis was predictive of preterm delivery (OR = 2.3, 95% CI: 1.5-3.3, p = 0.001). The incidence of respiratory distress syndrome (RDS), fetal growth restriction, fetal distress and preterm delivery were significantly higher in patients who were diagnosed before 30 weeks than after 34 weeks' gestation (p < 0.01). Gestational age at diagnosis is an important independent factor predicting adverse perinatal outcomes in patients with ICP.

Risk factors for adverse fetal outcomes among women with early- versus late-onset intrahepatic cholestasis of pregnancy

OBJECTIVE

To determine risk factors for adverse fetal outcomes (AFOs) among women with intrahepatic cholestasis of pregnancy (ICP) on the basis of time of onset.

METHODS

In a retrospective analysis, data were obtained for all women with ICP admitted to two centers in Guangzhou, China, between February 1, 1993, and January 31, 2014. Patients were divided into group A (early-onset ICP) and group B (late-onset ICP), and were further divided on the basis of severity. The frequency of AFOs was assessed.

RESULTS

Among 371 eligible women, 57 (15.4%) were in group A and 314 (84.6%) in group B. AFOs affected 20 (35.1%) women in group A and 67 (21.3%) in group B (P=0.024), and 12 (54.5%) of 22 women in group A and 21 (29.6%) of 71 in group B with severe ICP (P=0.032). Independent risk factors for AFO in group A were increased levels of serum bile acid (P=0.016) and alkaline phosphatase (P=0.004). Independent risk factors in group B were increased levels of alkaline phosphatase (P<0.001) and gamma-glutamyl transpeptidase (P=0.001).

CONCLUSION

Early-onset ICP is associated with a higher frequency of AFO than is late-onset ICP, especially in severe disease. The risk factors differ between early-onset and late-onset ICP.

Ursodeoxycholic acid combined with S-adenosylmethionine for treatment of severe intrahepatic cholestasis of pregnancy

AIM: To observe the clinical efficacy of ursodeoxycholic acid (UDCA) combined with S-adenosylmethionine (S-AMe) in the treatment of severe intrahepatic cholestasis of pregnancy (ICP).

METHODS: Eighty patients with severe ICP treated at our hospital were randomly divided into either an observation group or a control group. Both groups of patients received conventional therapy. The observation group was additionally given UDCA and S-AMe, and the control group was additionally given UDCA only. Pruritus score, liver function changes and perinatal adverse reactions were compared between the two groups.

RESULTS: After treatment, skin pruritus scores were significantly improved in both groups, and the improvement was significantly better in the observation group (0.79 ± 0.55 vs 1.20 ± 0.61, P < 0.05). The time to pruritus disappearance was significantly shorter in the observation group than in the control group (3.3 d ± 0.9 d vs 3.6 d ± 1.4 d, P < 0.05). Total bile acid, total bilirubin, direct bilirubin, aspartate aminotransferase, and alanine aminotransferase were significantly decreased in both groups after treatment, and the decreases were more significant in the observation group (P < 0.05). No neonatal death occurred in either group. The percentage of patients with cesarean section (30% vs 70%) and the incidences of neonatal asphyxia (0% vs 20%), fetal distress (25% vs 70%), meconium stained amniotic fluid (35% vs 65%) and postpartum hemorrhage (22.5% vs 55%) were significantly lower in the observation group than in the control group (P < 0.05 or P < 0.01).

CONCLUSION: Combined application of UDCA and S-AMe in the treatment of severe ICP can effectively relieve skin itching, reduce serum bile acid concentration, and improve the pregnancy outcome.

Intrahepatic cholestasis of pregnancy: Relationship between bile acid levels and maternal and fetal complications

Objective:

Intrahepatic cholestasis of pregnancy (ICP) complicates pregnancies which is characterized by elevated serum bile acid levels. ICP increases maternal and fetal morbidities. This study was designed to determine the association of maternal and fetal complications and serum bile acid levels.

Material and method:

Maternal and fetal characteristics were analyzed from the medical records of 61 patients who gave birth following a pregnancy complicated with ICP between 2009 and 2013.

Results:

Eighty seven percent of 61 cases were singletons, and 13% of them were twins. Mean SBA level was 36 μmol/L. Preterm birth rate among singletons and twin pregnancies were 24.5% and 62.5%, respectively. Mean SBA level in preterm birth group was statistically higher with respect to the term birth group (100.8 μmol/L and 25.61 μmol/L, respectively; p=0.001). No perinatal mortality associated with ICP was detected in the study group.

Conclusion:

Pregnant women with the ICP compose high-risk group in regard to fetal and maternal risks. Close follow-up of these patients is required due to increased risks such as preterm delivery, meconium staining and fetal death.

Primum non nocere: how active management became modus operandi for intrahepatic cholestasis of pregnancy

The Royal College of Obstetrics and Gynecology does not endorse routine active management of intrahepatic cholestasis of pregnancy (ICP)-affected pregnancies. In contrast, the American College of Obstetricians and Gynecologists supports active management protocols for ICP. To investigate this controversy, we evaluated the evidence supporting ICP as a medical indication for early term delivery and the evolution of active management protocols for ICP. Sixteen articles published between 1986 and 2011 were identified. We created 2 groups based on whether obstetric care included active management. Group 1 comprised 6 uncontrolled reports without active management that were published between 1967 and 1983 that described high perinatal mortality rates that primarily were related to prematurity sequel. This group became the fundamental 'core' evidence for ICP-associated stillbirths and by extrapolation justification for active management. Group 2 was comprised of 10 reports in which the authors credited empirically adopted active management with the observed low stillbirth rates in ICP-affected pregnancies. Although the group 1 articles routinely are cited as evidence of ICP-associated stillbirth risk, the 1.2% stillbirth rate (4/331) in this group is similar to the background stillbirth rates of 1.1% (11/1000) and 0.6% (6/1000) in 1967 and 2011, respectively (P = .062 and P = .0614, respectively). Likewise, the stillbirth rates for articles in group 2 were similar to their respective national stillbirth rate. Nevertheless, group 2 articles have become the evidence-based support for active management. We found no evidence to support the practice of active management for ICP.

Intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy is the most common pregnancy-specific liver disease that typically presents in the third trimester. The clinical features are maternal pruritus in the absence of a rash and deranged liver function tests, including raised serum bile acids. Intrahepatic cholestasis of pregnancy is associated with an increased risk of adverse perinatal outcomes, including spontaneous preterm delivery, meconium staining of the amniotic fluid, and stillbirth. It is commonly treated with ursodeoxycholic acid. There is accumulating evidence to suggest that intrahepatic cholestasis of pregnancy has a lasting influence on both maternal and fetal health. We review the etiology, diagnosis, and management of this intriguing condition.

Pregnancy-related liver disorders

Pregnancy-related liver disorders accounted for 8% of all maternal deaths at our center from 1999 to 2011. Of the three pregnancy-related liver disorders (acute fatty liver of pregnancy (AFLP), HELLP (Hemolysis, elevated liver enzymes, low platelets) syndrome and pre-eclamptic liver dysfunction, which can lead to adverse maternal and fetal outcome, AFLP is most typically under - diagnosed. Risk of maternal death can be minimised by timely recognition and early/aggressive multi-specialty management of these conditions. Urgent termination of pregnancy remains the cornerstone of therapy for some of these life threatening disorders, but recent advancements in our understanding help us in better overall management of these patients. This review focuses on various aspects of pregnancy-related liver disorders.

High concentraction of taurocholic acid induced apoptosis in HTR-8/SVneo cells via overexpression of ERp29 and activation of p38

INTRODUCTION

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific disease associated with a significant risk of fetal complications. Our previous study using an iTRAQ-based proteomics approach showed that ERp29 was overexpressed in the placenta tissue of ICP patients, which was an apoptosis-related protein and has not been investigated in the pathogenesis of ICP. The aim of this study was to explore the role of ERp29 in the mechanism of apoptosis in the placenta of ICP.

METHODS

HTR-8/SVneo cells were cultured and treated with different concentrations of taurocholic acid (TCA) (0, 10, 50 and 100 μM). The apoptotic index and cell cycle were detected by flow cytometry; furthermore, the expression levels of ERp29 and p-p38 were detected by western blot. The ERp29-siRNA was also used to confirm the role of ERp29 in TCA induced-apoptosis.

RESULTS

ERp29 expression and the apoptotic index were significantly increased in HTR-8/SVneo cells exposed to 100 μM TCA; so were p-p38 and caspase-3 activity, compared with the 50 μM, 10 μM TCA groups and negative control group (P < 0.05, respectively). The induction of apoptosis by TCA and the expression of p-p38 were reduced in HTR-8/SVneo cells after treatment with ERp29-siRNA, compared with controls (P < 0.05, respectively).

CONCLUSIONS

This study suggested that overexpression of ERp29 may play a key role in TCA-induced apoptosis in HTR-8/SVneo cells via activation of p38, which may participate in the pathogenesis of ICP and may represent a novel target for ICP treatment.

Association of severe intrahepatic cholestasis of pregnancy with adverse pregnancy outcomes: a prospective population-based case-control study

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific liver disease, characterized by maternal pruritus and raised serum bile acids. Our objectives were to describe the epidemiology and pregnancy complications associated with severe ICP and to test the hypothesis that adverse perinatal outcomes are increased in these women. A prospective population-based case-control study with national coverage was undertaken using the UK Obstetric Surveillance System (UKOSS). Control data for comparison were obtained from women with healthy pregnancy outcome through UKOSS (n = 2,232), St Mary's Maternity Information System (n = 554,319), and Office for National Statistics (n = 668,195). The main outcome measures investigated were preterm delivery, stillbirth, and neonatal unit admission. In all, 713 confirmed cases of severe ICP were identified, giving an estimated incidence of 9.2 per 10,000 maternities. Women with severe ICP and a singleton pregnancy (n = 669) had increased risks of preterm delivery (164/664; 25% versus 144/2200; 6.5%; adjusted odds ratio [OR] 5.39, 95% confidence interval [CI] 4.17 to 6.98), neonatal unit admission (80/654; 12% versus 123/2192; 5.6%; adjusted OR 2.68, 95% CI 1.97 to 3.65), and stillbirth (10/664; 1.5% versus 11/2205; 0.5%; adjusted OR 2.58, 95% CI 1.03 to 6.49) compared to controls. Seven of 10 stillbirths in ICP cases were associated with coexisting pregnancy complications. These differences remained significant against national data. Risks of preterm delivery, meconium-stained amniotic fluid, and stillbirth rose with increasing maternal serum bile acid concentrations.

CONCLUSION

In the largest prospective cohort study in severe ICP to date, we demonstrate significant increased risks of adverse perinatal outcomes, including stillbirth. Our findings support the case for close antenatal monitoring of pregnancies affected by severe ICP.

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.

Intrahepatic cholestasis of pregnancy is associated with an increased risk of gestational diabetes

OBJECTIVE

To evaluate the association between intrahepatic cholestasis of pregnancy (ICP) and gestational diabetes mellitus (GDM).

STUDY DESIGN

A retrospective case-control study of pregnancy outcomes in 57,724 women managed at a university teaching hospital in Rhode Island, USA, in whom universal screening for GDM had been performed and who were assessed for the incidence of ICP. Pregnancies complicated by ICP or GDM between February 2005 and June 2011 were identified from the electronic patient records using appropriate ICD codes. A total of 125 cases were required to detect a difference in the incidence of GDM in ICP at 5% significance with 80% power. Demographic and clinical outcome data (including maternal age, ethnic group, BMI, and infant weight and gender) were also collected.

RESULTS

Of the 57,724 pregnancies, 143 were complicated by ICP (0.25%) and 4880 by GDM (8.5%). Nineteen ICP cases had GDM. The incidence of GDM in ICP was 13.6% (19/140, OR 1.68 CI 1.04-2.72). Where gestational ages were available (n=105), of those screened for GDM prior to developing ICP, 13.4% (11/82, OR 1.64 CI 0.88-3.06) had a confirmed diagnosis, rising to 30% (7/23, OR 4.69 CI 1.98-11.1) in cases that were screened following the onset of cholestasis. Simple linear regression analysis of adjusted birth weight centiles in ICP revealed a significant linear trend of increasing centiles with gestational age (p=0.005).

CONCLUSIONS

These data support the hypothesis that the incidence of GDM is higher in women predisposed to developing ICP. It is likely that this susceptibility increases further following the onset of cholestasis.

The etiology of intrahepatic cholestasis of pregnancy: towards solving a monkey puzzle

Clinical and epidemiological findings implicate genetic predisposition and the effects of elevated steroids in pregnancy in the pathogenesis of intrahepatic cholestasis of pregnancy. To date, a number of studies have identified polymorphisms encoding biliary canalicular transporters, including those encoded by ABCB4 and ABCB11, which are associated with intrahepatic cholestasis of pregnancy. Questions remain regarding divergent findings between populations and the relative contributions of these polymorphisms. In a large study of Western European women with intrahepatic cholestasis of pregnancy, Dixon et al. (this issue) provide further insights into the genetics of this cholestatic syndrome, which contribute to ongoing evaluation of cholestasis generally.

Comparative proteomics analysis of placenta from pregnant women with intrahepatic cholestasis of pregnancy

Introduction

Intrahepatic cholestasis of pregnancy (ICP) usually occurs in the third trimester and associated with increased risks in fetal complications. Currently, the exact cause of this disease is unknown. In this study we aim to investigate the potential proteins in placenta, which may participate in the molecular mechanisms of ICP-related fetal complications using iTRAQ-based proteomics approach.

Methods

The iTRAQ analysis combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was performed to separate differentially expressed placental proteins from 4 pregnant women with ICP and 4 healthy pregnant women. Bioinformatics analysis was used to find the relative processes that these differentially expressed proteins were involved in. Three apoptosis related proteins ERp29, PRDX6 and MPO that resulted from iTRAQ-based proteomics were further verified in placenta by Western blotting and immunohistochemistry. Placental apoptosis was also detected by TUNEL assay.

Results

Proteomics results showed there were 38 differentially expressed proteins from pregnant women with ICP and healthy pregnant women, 29 were upregulated and 9 were downregulated in placenta from pregnant women with ICP. Bioinformatics analysis showed most of the identified proteins was functionally related to specific cell processes, including apoptosis, oxidative stress, lipid metabolism. The expression levels of ERp29, PRDX6 and MPO were consistent with the proteomics data. The apoptosis index in placenta from ICP patients was significantly increased.

Conclusion

This preliminary work provides a better understanding of the proteomic alterations of placenta from pregnant women with ICP and may provide us some new insights into the pathophysiology and potential novel treatment targets for ICP.

Liver diseases in pregnancy: Diseases unique to pregnancy

Pregnancy is a special clinical state with several normal physiological changes that influence body organs including the liver. Liver disease can cause significant morbidity and mortality in both pregnant women and their infants. This review summarizes liver diseases that are unique to pregnancy. We discuss clinical conditions that are seen only in pregnant women and involve the liver; from Hyperemesis Gravidarum that happens in 1 out of 200 pregnancies and Intrahepatic Cholestasis of Pregnancy (0.5%-1.5% prevalence), to the more frequent condition of preeclampsia (10% prevalence) and its severe form; hemolysis, elevated liver enzymes, and a low platelet count syndrome (12% of pregnancies with preeclampsia), to the rare entity of Acute Fatty Liver of Pregnancy (incidence of 1 per 7270 to 13000 deliveries). Although pathogeneses behind the development of these aliments are not fully understood, theories have been proposed. Some propose the special physiological changes that accompany pregnancy as a precipitant. Others suggest a constellation of factors including both the mother and her fetus that come together to trigger those unique conditions. Reaching a timely and accurate diagnosis of such conditions can be challenging. The timing of the condition in relation toward which trimester it starts at is a key. Accurate diagnosis can be made using specific clinical findings and blood tests. Some entities have well-defined criteria that help not only in making the diagnosis, but also in classifying the disease according to its severity. Management of these conditions range from simple medical remedies to measures such as immediate termination of the pregnancy. In specific conditions, it is prudent to have expert obstetric and medical specialists teaming up to help improve the outcomes.

Expression of corticotrophin-releasing hormone and its receptor in patients with intrahepatic cholestasis of pregnancy

OBJECTIVE

Intrahepatic cholestasis of pregnancy (ICP) is the most common pregnancy-specific liver disorders. Although various biological effects of corticotrophin-releasing hormone (CRH) has in pregnancy have been reported, its activities in patients with ICP are lacking. Here we evaluated CRH and its receptor (CRH-R1) expression in placenta and serum in control and ICP patients, to assess their potential activities in the ICP pathogenesis.

METHODS AND MATERIALS

Placental tissues were obtained from the control and ICP patients (10 cases for each group) between 37 and 39 gestational weeks. Immunohistochemistry, Western Blotting and real-time PCR analysis were used to detect the CRH and CRH-R1 expression in placenta. Meanwhile, maternal serums were analyzed for detecting CRH in the control and ICP patients (80 cases for each group) in 34-37 gestational weeks. All data were observed and recorded for comparing and analyzing in control and ICP patients.

RESULTS

CRH staining was found in syncytiotrophoblast and feto-placental vascular endothelium cells of placenta, whereas CRH-R1 staining was found in syncytiotrophoblast by using immunohistochemical analysis. The CRH expression level in ICP placenta was significantly lower than those results in controls (P < 0.01). For CRH-R1, CRH mRNA and CRH-R1 mRNA expressions, no statistical differences were found between control and ICP groups (all P > 0.05). Serum CRH levels increased in both control and ICP groups, but the growth rate was limited in ICP group, especially in late pregnancy (P < 0.05).

CONCLUSIONS

The down-regulation of CRH in ICP placentas and the limited growth rate of CRH in the maternal serum of ICP patients might impair the blood flow regulation of the utero-placental-fetal unit, which might result in poor fetoplacental vascular perfusion and adverse pregnancy outcomes. CRH might play a significant role in the pathogenesis of ICP and provide a new approach to further investigate the etiology of ICP.