Intrahepatic cholestasis of pregnancy: Amelioration of pruritus by UDCA is associated with decreased progesterone disulphates in urine

Intrahepatic cholestasis of pregnancy: Introduction and overview 2024

Considerable progress has been made to explain the aetiology of intrahepatic cholestasis of pregnancy (ICP) and of the adverse pregnancy outcomes associated with high maternal total serum bile acids (TSBAs). The reported thresholds for non-fasting TSBA associated with the risk of stillbirth and spontaneous preterm birth can be used to identify pregnancies at risk of these adverse outcomes to decide on appropriate interventions and to give reassurance to women with lower concentrations of TSBA. Data also support the use of ursodeoxycholic acid to protect against the risk of spontaneous preterm birth. A previous history of ICP may be associated with higher rates of subsequent hepatobiliary disease: if there is a suspicion of underlying susceptibility, clinicians caring for women with ICP should screen for associated disorders or for genetic susceptibility and, where appropriate, refer for ongoing hepatology review.

[Intrahepatic cholestasis of pregnancy: French College of Obstetricians and Gynecologists guidelines for clinical practice]

OBJECTIVE

To identify strategies for reducing neonatal and maternal morbidity associated with intrahepatic cholestasis pregnancy (ICP).

MATERIAL AND METHODS

The quality of evidence of the literature was assessed following the GRADE methodology with questions formulated in the PICO format (Patients, Intervention, Comparison, Outcome) and outcomes defined a priori and classified according to their importance. An extensive bibliographic search was performed on PubMed, Cochrane, EMBASE and Google Scholar databases. The quality of the evidence was assessed (high, moderate, low, very low) and a (i) strong or (ii) weak recommendations or (iii) no recommendation were formulated. The recommendations were reviewed in two rounds with external reviewers (Delphi survey) to select the consensus recommendations.

RESULTS

Of the 14 questions (from 12 PICO questions and one definition question outside the PICO format), there was agreement between the working group and the external reviewers on 14 (100%). The level of evidence of the literature was insufficient to provide a recommendation on two questions. ICP is defined by the occurrence of suggestive pruritus (palmoplantar, nocturnal) associated with a total bile acid level>10μmol/L or an alanine transaminase level above 2N after ruling out differential diagnoses. In the absence of suggestive symptoms of a differential diagnosis, it is recommended not to carry out additional biological or ultrasound tests. In women with CIP, ursodeoxycholic acid is recommended to reduce the intensity of maternal pruritus (Strong recommendation. Quality of the evidence moderate) and to decrease the level of total bile acids and alanine transaminases. (Strong recommendation. Quality of the evidence moderate). S-adenosyl-methionine, dexamethasone, guar gum or activated charcoal should not be used to reduce the intensity of maternal pruritus (Strong recommendation. Quality of evidence low), and there is insufficient data to recommend the use of antihistamines (No recommendation. Quality of evidence low). Rifampicin (Weak recommendation. Very low quality of evidence) or plasma exchange (Strong recommendation. Very low quality of evidence) should not be used to reduce maternal pruritus and perinatal morbidity. Serum monitoring of bile acids is recommended to reduce perinatal morbidity and mortality (stillbirth, prematurity) (Low recommendation. Quality of the evidence low). The level of evidence is insufficient to determine whether fetal heart rate or fetal ultrasound monitoring are useful to reduce perinatal morbidity (No recommendation). Birth is recommended when bile acid level is above 99μmol/L from 36 weeks gestation to reduce perinatal morbidity, in particular stillbirth. When bile acid level is above 99μmol/L is below 100μmol/L, women should be informed that induction of labor could be considered 37 and 39 weeks gestation to reduce perinatal morbidity. (Strong recommendation. Quality of evidence low). In postpartum, total bile acids and alanine transaminases level should be checked and normalized before prescribing estrogen-progestin contraception, ideally with a low estrogen dose (risk of recurrence of pruritus and cytolysis) (Low recommendation. Quality of evidence very low).

CONCLUSION

Although the quality of evidence regarding ICP gestational cholestasis remains low, there is a strong consensus in France, as shown by our Delphi study, on how to manage women with ICP. The reference first-line treatment is ursodeoxycholic acid.

Recurrent Intrahepatic Cholestasis of Pregnancy with History of Fetal Demise

Intrahepatic cholestasis of pregnancy (ICP) is a rare, potentially fatal liver disorder that occurs in late pregnancy. It is characterized by pruritus, jaundice, and elevated liver enzymes, with spontaneous relief of signs and symptoms after birth. Early detection and treatment are required due to the potential risk of fetal complications, including fetal death. A 30-year-old woman with deeply icteric sclera and skin scratch marks presented to a gastroenterology-hepatology referral clinic. Her liver enzymes, bilirubin levels, and serum bile acid levels were all abnormally high. She also disclosed similar symptoms in her previous pregnancy, which resulted in fetal death at the sixth month. With a presumptive diagnosis of recurrent ICP, the patient was started on ursodeoxycholic acid (UDCA) pills, which significantly improved her pruritus and returned her bile acid levels to normalcy after 2 months of treatment. The delivery was uneventful. We believe that a proper diagnosis combined with UDCA treatment and vigilant obstetric follow-up significantly reduced the patient's symptoms and prevented a possible intrauterine death.

SWATH proteomics analysis of placental tissue with intrahepatic cholestasis of pregnancy

INTRODUCTION

Intrahepatic cholestasis of pregnancy (ICP) usually occurs in the second and third trimesters. The disease's etiology and diagnostic criteria are currently unknown. Based on a sequence window to obtain all theoretical fragment ions (SWATH) proteomic approach, this study sought to identify potential proteins in placental tissue that may be involved in the pathogenesis of ICP and adverse fetal pregnancy outcomes.

METHODS

The postpartum placental tissue of pregnant women with ICP were chosen as the case group (ICP group) (subdivided into mild ICP group (MICP group) and severe ICP group (SICP group)), and healthy pregnant women were chosen as the control group (CTR). The hematoxylin-eosin (HE) staining was used to observe the histologic changes of placenta. The SWATH analysis combined with liquid chromatography-tandem mass spectrometry (LC-MS) was used to screen the differentially expressed proteins (DEPs) in ICP and CTR groups, and bioinformatics analysis was used to find out the biological process of these differential proteins.

RESULTS

Proteomic studies showed there were 126 DEPs from pregnant women with ICP and healthy pregnant women. Most of the identified proteins were functionally related to humoral immune response, cell response to lipopolysaccharide, antioxidant activity and heme metabolism. A subsequent examination of placentas from patients with mild and severe ICP revealed 48 proteins that were differentially expressed. Through death domain receptors and fibrinogen complexes, these DEPs primarily regulate extrinsic apoptotic signaling pathways, blood coagulation, and fibrin clot formation. The differential expressions of HBD, HPX, PDE3A, and PRG4 were down-regulated by Western blot analysis, which was consistent with proteomics.

DISCUSSION

This preliminary study helps us to understand the changes in the placental proteome of ICP patients, and provides new insights into the pathophysiology of ICP.

Pruritus in Chronic Liver Disease

Pruritus can be associated with chronic liver disease, particularly cholestatic liver disease. Although the pathophysiology is uncertain, there are a few proposed mechanisms and much is still being discovered. Workup involves an assessment to rule out a dermatologic, neurologic, psychogenic, or other underlying systemic disorder. First-line therapy is cholestyramine, which is generally well tolerated and effective. In those who fail cholestyramine, alternative drugs including rifampicin and μ-opioid receptor antagonists can be considered. If medical therapy is ineffective and pruritus is significant, alternative experimental therapies such as albumin dialysis, photopheresis, plasmapheresis, and biliary diversion can be considered.

Recognizing skin conditions in patients with cirrhosis: a narrative review

Background: The skin is a major target organ for extrahepatic manifestations of liver diseases, and dermatologic abnormalities are common in patients with hepatic disorders. Clinical examination of the skin, nails and hair can allow for appropriate recognition, early diagnosis and treatment of liver diseases, and improvement in the quality of life and life expectancy of affected patients.Methods: We searched 3 databases (Pubmed,Medline and Embase) and selected studies about cirrhosis related skin manifestations and their pathophysiology.Results: A total of 73 articles were included in the review. Studies displayed the spectrum of cutaneous manifestations related to hormonal and vascular changes as well as nail and hair changes in patients with cirrhosis and/or portal hypertension.Conclusion: Cutaneous alterations are important clues or potential indications in the diagnosis of liver cirrhosis. Familiarity with skin conditions can be promptly diagnosed and appropriate management initiated.KEY MESSAGESManifestations of the liver and skin disorders are interrelated in various ways. Cutaneous changes may be the first clue that a patient has liver disease.The skin is a major target organ for extrahepatic manifestations of liver diseases. A broad range of cutaneous alterations can be present in patients with cirrhosis, such as vascular, nail, hair, hormonal changes, etc.Recognizing these signs is crucial so that potential underlying diseases including liver disease can be promptly diagnosed and appropriate management timely initiated.

Cholestatic Itch: Our Current Understanding of Pathophysiology and Treatments

Hepatic pruritus is common in liver conditions, including cholestasis and nonalcoholic fatty liver disease. The pruritus can be severe enough to diminish sleep and decrease quality of life. The pathophysiology likely involves many molecules and receptors, including bile acids, bilirubin, lysophosphatidic acid (LPA), endogenous opioids, and serotonin. Recent advances suggest a significant role of Mas-related G protein-coupled receptor X4 (MRGPRX4) and autotaxin/LPA as key players in cholestatic pruritus. Further research is needed to develop increasingly targeted therapies with greater efficacy, especially given that many patients report itch refractory to various treatments. Cholestyramine was the only US FDA-approved drug for cholestatic pruritus until recent approval of ileal bile acid transporter (IBAT) inhibitors for use in the pediatric cholestatic conditions, progressive familial intrahepatic cholestasis and Alagille syndrome. Both medications decrease the bile acid pool. IBAT inhibitors are under investigation for broader use, and targeting LPA receptors and MRGPR4 are additional attractive options.

Alpha-1 Antitrypsin Z Variant (AAT PI*Z) as a Risk Factor for Intrahepatic Cholestasis of Pregnancy

Background: Intrahepatic cholestasis of pregnancy (ICP; prevalence 0.2–15.6%) is the most common pregnancy-related liver disorder. It may have serious consequences for a pregnancy, including increased risk of preterm delivery, meconium staining of amniotic fluid, fetal bradycardia, distress, and fetal demise. In cases of high bile acids (>100μmol/L), patients have 10-fold increase in the risk of stillbirth. Biophysical methods of fetal monitoring, such as cardiotocography, ultrasonography, or Doppler have been proven unreliable for risk prediction in the course of intrahepatic cholestasis. Therefore, we believe extensive research for more specific, especially early, markers should be carried out. By analogy with cholestasis in children with inherited alpha-1 antitrypsin deficiency (AATD), we hypothesized the SERPINA1 Z pathogenic variant might be related to a higher risk of cholestasis in pregnancy. This study aimed to investigate the most common AATD variants (Z and S SERPINA1 alleles) in a group of cholestatic pregnant women.

Results: The Z carrier frequency was calculated to be 6.8%, which is much higher compared to the general population [2.3%; the Chi-squared test with Yates correction is 6.8774 (p=0.008)].

Conclusion: Increased prevalence of SERPINA1 PI*Z variant in a group of women with intrahepatic cholestasis may suggest a possible genetic origin of a higher risk of intrahepatic cholestasis in pregnancy.

Doxycycline-induced cholestatic liver injury

Doxycycline-induced liver injury is a rare phenomenon, with an unclear clinical course and etiopathogenesis. The onset of injury may be acute-to-subacute, with a pattern ranging from hepatocellular or cholestatic to mixed, and it often lasts up to several weeks. We present a case of cholestatic liver injury secondary to doxycycline use in a middle-aged woman. In patients with a history of doxycycline exposure and subsequent hepatic injury, an adverse drug reaction due to doxycycline should remain on the differential, and immediate removal of the offending agent with close monitoring of the clinical condition should be pursued.

Associations between Maternal Lipid Profiles and Pregnancy Complications: A Prospective Population-Based Study

OBJECTIVE

To investigate whether plasma lipid profiles are independently associated with pregnancy complications including gestational diabetes mellitus (GDM), hypertensive disorder complicating pregnancy (HDCP), and intrahepatic cholestasis of pregnancy (ICP).

STUDY DESIGN

A prospective study was conducted among 1,704 pregnant women at three medical institutions in Chengdu, China. The concentrations of triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were measured at gestational weeks 12 ± 1, 24 ± 1, and 34 ± 1. Logistic regression models were used to estimate the association between lipid profiles and pregnancy complications. Receiver operating characteristic analysis was performed to determine the value of lipid profiles to predict GDM and HDCP.

RESULTS

After adjusting for potential confounders, TG, TC, and LDL-C in the first trimester were independently associated with GDM (TG: odds ratio [OR] =2.00, 95% confidence interval [CI]: 1.57-2.56; TC: OR = 1.38, 95% CI: 1.16-1.64; LDL-C: OR = 1.43, 95% CI: 1.14-1.79) and HDCP (TG: OR = 2.42, 95% CI: 1.56-3.78, TC: OR = 1.64, 95% CI: 1.04-2.57; LDL-C: OR = 1.87, 95% CI: 1.07-3.25). The TC concentration during the whole pregnancy (first trimester: OR = 1.53, 95% CI: 1.13-2.08; second trimester: OR = 1.31, 95% CI: 1.06-1.61; third trimester: OR = 1.39, 95% CI: 1.17-2.04) and LDL-C in the last two trimesters (second trimester: OR = 1.62, 95% CI: 1.30-2.04; third trimester: OR = 1.56, 95% CI: 1.29-1.88) were positively associated with ICP. HDL-C in the third trimester was negatively associated with the risk of ICP (OR = 0.46, 95% CI: 0.22-0.98). Combining lipid profiles in the first trimester with the other common predictors to predict GDM or HDCP owned stronger predictive power with the largest area under the curve (GDM: 0.643 [95% CI: 0.613-0.673], HDCP: 0.707 [95% CI: 0.610-0.804]) than either indicator alone.

CONCLUSION

Maternal lipid profiles during the whole pregnancy are significantly associated with GDM, HDCP, and ICP. Combining lipid profiles in the first trimester with the other common predictors could effectively improve the power of predicting GDM and HDCP.

Molecular Pathogenesis of Intrahepatic Cholestasis of Pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific liver disease. The maternal symptoms are characterized by skin pruritus and elevated bile acids, causing several adverse outcomes for fetuses, including an increased risk of preterm birth, meconium-stained amniotic fluid, neonatal depression, respiratory distress syndrome, and stillbirth. Genetic, hormonal, immunological, and environmental factors contribute to the pathogenesis of ICP, and the estrogen-bile acid axis is thought to play a dominant role. The advances in the past 10 years uncover more details of this axis. Moreover, dysregulation of extracellular matrix and oxygen supply, organelle dysfunction, and epigenetic changes are also found to cause ICP, illuminating more potential drug targets for interfering with. Here, we summarize the molecular pathogenesis of ICP with an emphasis on the advancement in the past 10 years, aiming to give an updated full view of this field.

Reduced spontaneous itch in mouse models of cholestasis

Pruritus is one of the most distressing symptoms in cholestatic patients. Plasma autotaxin (ATX) activity correlates with the severity of pruritus in cholestatic patients, but the pathophysiology is unclear. To study pruritus in mice, we measured scratch activity in cholestatic Atp8b1 mutant mice, a model for Progressive Familial Intrahepatic Cholestasis type 1, and wild type mice (WT) with alpha-naphthylisothiocyanate (ANIT)-induced cholestasis. To induce cholestasis, Atp8b1 mutant mice received a diet containing 0.1% cholic acid (CA) and WT mice were treated with ANIT. In these mice ATX was also overexpressed by transduction with AAV-ATX. Scratch activity was measured using an unbiased, electronic assay. Marked cholestasis was accomplished in both Atp8b1 mutant mice on a CA-supplemented diet and in ANIT-treatment in WT mice, but scratch activity was decreased rather than increased while plasma ATX activity was increased. Plasma ATX activity was further increased up to fivefold with AAV-ATX, but this did not induce scratch activity. In contrast to several reports two cholestatic mouse models did not display increased scratch activity as a measure of itch perception. Increasing plasma ATX activity by overexpression also did not lead to increased scratch activity in mice. This questions whether mice are suitable to study cholestatic itch.

Cholestasis-Associated Pruritus and Its Pruritogens

Pruritus is a debilitating symptom of various cholestatic disorders, including primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC) and inherited progressive familial intrahepatic cholestasis (PFIC). The molecular mechanisms leading to cholestasis-associated pruritus are still unresolved and the involved pruritogens are indecisive. As a consequence of pruritus, patients suffer from sleep deprivation, loss of daytime concentration, auto-mutilation and sometimes even suicidal ideations. Current guideline-approved therapy of cholestasis-associated pruritus includes stepwise administration of several medications, which may alleviate complaints in some, but not all affected patients. Therefore, also experimental therapeutic approaches are required to improve patients' quality of life. This article reviews the current state of research on pruritogens and their receptors, and shortly discusses the most recent experimental therapies.

Pharmacological interventions for treating intrahepatic cholestasis of pregnancy

BACKGROUND

Intrahepatic cholestasis of pregnancy (ICP) is a liver disorder that can develop in pregnancy. It occurs when there is a build-up of bile acids in the maternal blood. It has been linked to adverse maternal and fetal/neonatal outcomes. As the pathophysiology is poorly understood, therapies have been largely empiric. As ICP is an uncommon condition (incidence less than 2% a year), many trials have been small. Synthesis, including recent larger trials, will provide more evidence to guide clinical practice. This review is an update of a review first published in 2001 and last updated in 2013.

OBJECTIVES

To assess the effects of pharmacological interventions to treat women with intrahepatic cholestasis of pregnancy, on maternal, fetal and neonatal outcomes.

SEARCH METHODS

For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (13 December 2019), and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials, including cluster-randomised trials and trials published in abstract form only, that compared any drug with placebo or no treatment, or two drug intervention strategies, for women with a clinical diagnosis of intrahepatic cholestasis of pregnancy.

DATA COLLECTION AND ANALYSIS

The review authors independently assessed trials for eligibility and risks of bias. We independently extracted data and checked these for accuracy. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 26 trials involving 2007 women. They were mostly at unclear to high risk of bias. They assessed nine different pharmacological interventions, resulting in 14 different comparisons. We judged two placebo-controlled trials of ursodeoxycholic acid (UDCA) in 715 women to be at low risk of bias. The ten different pharmacological interventions were: agents believed to detoxify bile acids (UCDA) and S-adenosylmethionine (SAMe); agents used to bind bile acids in the intestine (activated charcoal, guar gum, cholestyramine); Chinese herbal medicines (yinchenghao decoction (YCHD), salvia, Yiganling and Danxioling pill (DXLP)), and agents aimed to reduce bile acid production (dexamethasone) Compared with placebo, UDCA probably results in a small improvement in pruritus score measured on a 100 mm visual analogue scale (VAS) (mean difference (MD) -7.64 points, 95% confidence interval (CI) -9.69 to -5.60 points; 2 trials, 715 women; GRADE moderate certainty), where a score of zero indicates no itch and a score of 100 indicates severe itching. The evidence for fetal distress and stillbirth were uncertain, due to serious limitations in study design and imprecision (risk ratio (RR) 0.70, 95% CI 0.35 to 1.40; 6 trials, 944 women; RR 0.33, 95% CI 0.08 to 1.37; 6 trials, 955 women; GRADE very low certainty). We found very few differences for the other comparisons included in this review. There is insufficient evidence to indicate if SAMe, guar gum, activated charcoal, dexamethasone, cholestyramine, Salvia, Yinchenghao decoction, Danxioling and Yiganling, or Yiganling alone or in combination are effective in treating women with intrahepatic cholestasis of pregnancy.

AUTHORS' CONCLUSIONS

When compared with placebo, UDCA administered to women with ICP probably shows a reduction in pruritus. However the size of the effect is small and for most pregnant women and clinicians, the reduction may fall below the minimum clinically worthwhile effect. The evidence was unclear for other adverse fetal outcomes, due to very low-certainty evidence. There is insufficient evidence to indicate that SAMe, guar gum, activated charcoal, dexamethasone, cholestyramine, YCHD, DXLP, Salvia, Yiganling alone or in combination are effective in treating women with cholestasis of pregnancy. There are no trials of the efficacy of topical emollients. Further high-quality trials of other interventions are needed in order to identify effective treatments for maternal itching and preventing adverse perinatal outcomes. It would also be helpful to identify those women who are mostly likely to respond to UDCA (for example, whether bile acid concentrations affect how women with ICP respond to treatment with UDCA).

Intrahepatic Cholestasis in Pregnancy: Review of the Literature

Intrahepatic cholestasis of pregnancy (ICP) is the most common hepatic disorder related to pregnancy in women. It usually develops within the third trimester of pregnancy and presents with pruritus as well as elevated levels of bile acid and/or alanine aminotransferase. Clinical signs quickly resolve after delivery; however, there is a high risk of the disorder recurring in subsequent pregnancies. ICP is associated with an increased risk of perinatal complications (premature birth, respiratory disorders, even stillbirth). Elevated levels of gestational hormones and genetic predispositions are important factors for the development of ICP; among the latter, mutations in hepatobiliary transport proteins (multidrug resistance protein 3-MDR3, bile salt export pump- BSEP) play a major role. Clinical and biochemical symptoms of ICP include pruritus and increased levels of total bile acids (TBA). Serum levels of TBA should be monitored in ICP patients throughout the pregnancy as concentrations above 40 μmol/L, which define that severe ICP isassociated with an increased risk of fetal complications. Therapeutic management is aimed at reducing the clinical symptoms, normalizing maternal biochemistry and preventing complications to the fetus. Pharmacological treatment of intrahepatic cholestasis of pregnancy consists of the administration of ursodeoxycholic acid to lower the levels of TBA and possibly reduce pruritus. If the treatment fails, premature delivery should be considered.

The Role of the Sodium-taurocholate Co-transporting Polypeptide (NTCP) and Bile Salt Export Pump (BSEP) in Related Liver Disease

BACKGROUND

Sodium Taurocholate Co-transporting Polypeptide (NTCP) and Bile Salt Export Pump (BSEP) play significant roles as membrane transporters because of their presence in the enterohepatic circulation of bile salts. They have emerged as promising drug targets in related liver disease.

METHODS

We reviewed the literature published over the last 20 years with a focus on NTCP and BSEP.

RESULTS

This review summarizes the current perception about structure, function, genetic variation, and regulation of NTCP and BSEP, highlights the effects of their defects in some hepatic disorders, and discusses the application prospect of new transcriptional activators in liver diseases.

CONCLUSION

NTCP and BSEP are important proteins for transportation and homeostasis maintenance of bile acids. Further research is needed to develop new models for determining the structure-function relationship of bile acid transporters and screening for substrates and inhibitors, as well as to gain more information about the regulatory genetic mechanisms involved in the processes of liver injury.

MRGPRX4 is a G protein-coupled receptor activated by bile acids that may contribute to cholestatic pruritus

Patients suffering from cholestasis, the slowing or stoppage of bile flow, commonly report experiencing an intense, chronic itch. Numerous pruritogens are up-regulated in cholestatic patient sera, including bile acids (BAs). Acute injection of BAs results in itch in both mice and humans, and BA-modulating therapy is effective in controlling patient itch. Here, we present evidence that human sensory neuron-expressed Mas-related G protein-coupled receptor X4 (MRGPRX4), an orphan member of the Mrgpr family of GPCRs, is a BA receptor. Using Ca2+ imaging, we determined that pathophysiologically relevant levels of numerous BAs activated MRGPRX4. No mouse Mrgpr orthologs were activated by BAs. To assess the in vivo relevance of BA activation of MRGPRX4, we generated a humanized mouse with targeted expression of MRGPRX4 in itch-encoding sensory neurons. BAs activated MRGPRX4+ sensory neurons at higher levels compared with WT neurons. Compared with control animals, MRGPRX4+ mice scratched more upon acute injection of BAs and in a model of cholestatic itch. Overall, these data suggest that targeting MRGPRX4 is a promising strategy for alleviating cholestatic itch.

Lysophosphatidic acid activates satellite glia cells and Schwann cells

Pruritus is a common and disabling symptom in patients with hepatobiliary disorders, particularly in those with cholestatic features. Serum levels of lysophosphatidic acid (LPA) and its forming enzyme autotaxin were increased in patients suffering from hepatic pruritus, correlated with itch severity and response to treatment. Here we show that in a culture of dorsal root ganglia LPA 18:1 surprisingly activated a large fraction of satellite glia cells, and responses to LPA 18:1 correlated inversely with responses to neuronal expressed transient receptor potential channels. LPA 18:1 caused only a marginal activation of heterologously expressed TRPV1, and responses in dorsal root ganglion cultures from TRPV1-deficient mice were similar to controls. LPA 18:1 desensitized subsequent responsiveness to chloroquine and TGR5 agonist INT-777. The LPA 18:1-induced increase in cytoplasmatic calcium stems from the endoplasmatic reticulum. LPA receptor expression in dorsal root ganglia and Schwann cells, LPAR1 immunohistochemistry, and pharmacological results indicate a signaling pathway through LPA receptor 1. Peripheral rat Schwann cells, which are of glial lineage as the satellite glia cells, were also responsive to LPA 18:1. Summarizing, LPA 18:1 primarily activates rather glial cells than neurons, which may subsequently modulate neuronal responsiveness and sensory sensations such as itch and pain.

May circulating steroids reveal a predisposition to intrahepatic cholestasis of pregnancy in non-pregnant women?

Intrahepatic cholestasis of pregnancy (ICP) is a frequent liver disorder, mostly occurring in the third trimester. ICP is not harmful to the mothers but threatens the fetus. The authors evaluated steroid alterations in maternal and mixed umbilical blood to elucidate their role in the ICP development. Ten women with ICP were included in the study. Steroids in the maternal blood were measured by Gas Chromatography-Mass Spectrometry (GC-MS) (n=58) and RIA (n=5) at the diagnosis of ICP, labor, day 5 postpartum, week 3 postpartum and week 6 postpartum. The results were evaluated by ANOVA consisting of the subject factor, between subject factors ICP, gestational age at the diagnosis of ICP and gestational age at labor, within-subject factor Stage and ICP × Stage interaction. The 17 controls were firstly examined in the week 36 of gestation. ICP patients showed reduced CYP17A1 activity in the C17,20 lyase step thus shifting the balance between the toxic conjugated pregnanediols and harmless sulfated 5alpha/beta-reduced-17-oxo C19 steroids. Hence, more toxic metabolites originating in maternal liver from the placental pregnanes may penetrate backward to the fetal circulation. As these alterations persist in puerperium, the circulating steroids could be potentially used for predicting the predisposition to ICP even before next pregnancy.

Therapeutic plasma exchange as a novel treatment for severe intrahepatic cholestasis of pregnancy: Case series and mechanism of action

INTRODUCTION

Intrahepatic cholestasis of pregnancy is characterised by pruritus and elevated serum bile acids. The pruritus can be severe, and pharmacological options achieve inconsistent symptomatic improvement. Raised bile acids are linearly associated with adverse fetal outcomes, with existing management of limited benefit. We hypothesised that therapeutic plasma exchange removes pruritogens and lowers total bile acid concentrations, and improves symptoms and biochemical abnormalities in severe cases that have not responded to other treatments.

METHODS

Four women with severe pruritus and hypercholanemia were managed with therapeutic plasma exchange. Serial blood biochemistry and visual analogue scores of itch severity were obtained. Blood and waste plasma samples were collected before and after exchange; individual bile acids and sulfated progesterone metabolites were measured with HPLC-MS, autotaxin activity and cytokine profiles with enzymatic methods. Results were analysed using segmental linear regression to describe longitudinal trends, and ratio t tests.

RESULTS

Total bile acids and visual analogue itch scores demonstrated trends to transiently improve following plasma exchange, with temporary symptomatic benefit reported. Individual bile acids (excluding the drug ursodeoxycholic acid), and the sulfated metabolites of progesterone reduced following exchange (P = .03 and P = .04, respectively), whilst analysis of waste plasma demonstrated removal of autotaxin and cytokines.

CONCLUSIONS

Therapeutic plasma exchange can lower potentially harmful bile acids and improve itch, likely secondary to the demonstrated removal of pruritogens. However, the limited current experience and potential complications, along with minimal sustained symptomatic benefit, restrict its current use to women with the most severe disease for whom other treatment options have been exhausted.

Could first- and second-trimester biochemical markers for Down syndrome have a role in predicting intrahepatic cholestasis of pregnancy?

INTRODUCTION

The aim of this study is to compare first- and second-trimester Down syndrome biochemical screening markers in intrahepatic cholestasis of pregnancy (ICP) and normal pregnancies.

MATERIAL AND METHODS

This observational case-control study was conducted at Health Sciences University Zeynep Kamil Maternity and Children's Health Training and Research Hospital and the Department of Obstetrics and Gynecology at Erciyes University Medical Faculty during 2016-2017. The study included 165 patients, and consisted of 62 women who had been diagnosed with ICP (the ICP-diagnosed group) and 103 healthy pregnant women (the control group). First-trimester free β-human chorionic gonadotropin (β-hCG), pregnancy-associated plasma protein-A (PAPP-A) and second-trimester total β-hCG, estriol (E3), α-fetoprotein (AFP), and inhibin A levels were compared between the two groups.

RESULTS

The mean patient age was 28.67 ±5.96 years, with no significant difference between the groups (p > 0.05). Average PAPP-A levels were significantly lower in the ICP-diagnosed group (p < 0.001). When the cut-off value for PAPP-A was taken as ≤ 0.93 multiple of median (MoM), the sensitivity and specificity values for ICP were 73.8% and 56.3%, respectively (95% CI, AUC ± SE: 0.663 ±0.042).

CONCLUSIONS

The decrease in PAPP-A MoM value indicates an increase in the risk of developing ICP, while changes in other markers were not sufficient to predict ICP.

Pruritus: Progress toward Pathogenesis and Treatment

Pruritus, the most common cutaneous symptom, is widely seen in many skin complaints. It is an uncomfortable feeling on the skin and sometimes impairs patients' quality of life. At present, the specific mechanism of pruritus still remains unclear. Antihistamines, which are usually used to relieve pruritus, ineffectively work in some patients with itching. Recent evidence has suggested that, apart from histamine, many mediators and signaling pathways are involved in the pathogenesis of pruritus. Various therapeutic options for itching correspondingly have been developed. In this review, we summarize the updated pathogenesis and therapeutic strategies for pruritus.

Bile acid levels and risk of adverse perinatal outcomes in intrahepatic cholestasis of pregnancy: A meta-analysis

AIM

We aimed to determine the association between maternal total bile acid (TBA) levels and the risks of adverse perinatal outcomes in pregnant women with intrahepatic cholestasis of pregnancy (ICP) based on a meta-analysis study.

METHODS

We searched PubMed for articles published from 2000 to 2015 with a focus on ICP and restriction to the English language. The main perinatal outcomes were preterm birth (PTB), meconium-stained amniotic fluid (MSAF), asphyxia, or respiratory distress syndrome (RDS). Relative risk (RR) with 95% confidence intervals (CI) was the summary statistic. We used a random- or fixed-effects model to calculate the pooled RR according to the heterogeneity test. Subgroup analyses were performed by region and study design.

RESULTS

Nine eligible related citations fulfilled the inclusion criteria and were included in this study. Compared with pregnant women with a serum TBA < 40 μmol/L, severe ICP (TBA ≥ 40 μmol/L) was associated with a significantly increased risk of adverse fetal outcomes (pooled RR, 1.96; 95%CI, 1.63-2.35), PTB (pooled RR, 2.23; 95%CI, 1.51-3.29), MSAF (pooled RR, 2.27; 95%CI, 1.81-2.85), and asphyxia or RDS (pooled RR, 1.67; 95%CI, 1.18-2.36). Sensitivity analysis suggested that the study design difference may be a major source of heterogeneity. No publication bias was demonstrated by Begg's test (P > 0.05).

CONCLUSION

This meta-analysis indicates that maternal elevated bile acid levels are significantly associated with increased risks of overall adverse perinatal outcomes, PTB, MSAF, and asphyxia or RDS. Serum TBA levels seem to be a useful predictor for the risk of adverse perinatal outcomes.

Pregnancy and bile acid disorders

During pregnancy, extensive adaptations in maternal metabolic and immunological physiology occur. Consequently, preexisting disease may be exacerbated or attenuated, and new disease susceptibility may be unmasked. Cholestatic diseases, characterized by a supraphysiological raise in bile acid levels, require careful monitoring during pregnancy. This review describes the latest advances in the knowledge of intrahepatic cholestasis of pregnancy (ICP), the most common bile acid disorder specific to pregnancy, with a focus on the disease etiology and potential mechanisms of ICP-associated adverse pregnancy outcomes, including fetal demise. The course of preexisting cholestatic conditions in pregnancy is considered, including primary sclerosing cholangitis, primary biliary cholangitis, biliary atresia, and Alagille syndrome. The currently accepted treatments for cholestasis in pregnancy and promising new therapeutics for the condition are described.

Bile acids and gestation

There are numerous profound maternal physiological changes that occur from conception onwards and adapt throughout gestation in order to support a healthy pregnancy. By the time of late gestation, when circulating pregnancy hormones are at their highest concentrations, maternal adaptations include relative hyperlipidemia, hypercholanemia and insulin resistance. Bile acids have now been established as key regulators of metabolism, and their role in gestational changes in metabolism is becoming apparent. Bile acid homeostasis is tightly regulated by the nuclear receptor FXR, which has been shown to have reduced activity during pregnancy. This review focuses on the gestational alterations in bile acid homeostasis that occur in normal pregnancy, which in some women can become pathological, leading to the development of intrahepatic cholestasis of pregnancy. As well as their important role in maternal metabolic health, we will review bile acid metabolism in the feto-placental unit.

Relationship between early onset severe intrahepatic cholestasis of pregnancy and higher risk of meconium-stained fluid

Background

Intrahepatic cholestasis of pregnancy (ICP) is the commonest gestational liver disease. The risk of adverse fetal outcome has been associated with the severity of maternal hypercholanemia after diagnosis.

Objective

To investigate whether there is a relationship between the severity and timing of onset of hypercholanemia and the risk of meconium-stained amniotic fluid (MSAF) and adverse neonatal events.

Study design

The study included 382 pregnancies complicated by ICP managed at a referral hospital in Buenos Aires (Argentina) between June 2009 and December 2013. The patients were classified into three groups according to the severity of hypercholanemia at diagnosis; mild (10–19.9 μmol/L), moderate (20–39.9 μmol/L) and severe (≥40 μmol/L). Their clinical characteristics and pregnancy outcomes were investigated in a prospective observational study.

Results

Higher risk of MSAF was observed when ICP appeared early in gestation or when hypercholanemia was more severe. Taking both parameters into account an MSAF risk factor (MRF) was defined. Based on a model of positive/negative predictive values, a cut-off point of MRF = 3 was selected, which prioritized sensitivity versus specificity. In ICP patients with MRF>3, the probability of MSAF was enhanced 4-fold. An increase in the frequency of MSAF was also associated with higher serum levels at diagnosis of alanine transaminase, alkaline phosphatase and direct bilirubin.

Conclusions

The risk of MSAF is associated not only with the magnitude of hypercholanemia at diagnosis but also with the early gestational onset of raised maternal serum bile acids.

The role of steroid hormones in the development of intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is a disorder of liver function, commonly occurring in the third trimester but sometimes also as soon as the end of the second trimester of pregnancy. Symptoms of this disorder include pruritus, plus abnormal values of bile acids and hepatic transaminases. After birth, symptoms disappear and liver function returns to normal. Though ICP is relatively non-complicated and often symptomatically mild from the point-of-view of the mother, it presents a serious risk to the fetus, making this disease the subject of great interest. The etiology and pathogenesis of ICP is multifactorial and as yet not fully elucidated. Hormonal factors likely play a significant role, along with genetic as well as exogenous factors. Here we summarize the knowledge of changes in steroid hormones and their role in the development of intrahepatic cholestasis of pregnancy. In addition, we consider the role of exogenous factors as possible triggers of steroid hormone changes, the relationship between metabolic steroids and bile acids, as well as the combination of these factors in the development of ICP in predisposed pregnant women.

A Comprehensive Evaluation of Steroid Metabolism in Women with Intrahepatic Cholestasis of Pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is a common liver disorder, mostly occurring in the third trimester. ICP is defined as an elevation of serum bile acids, typically accompanied by pruritus and elevated activities of liver aminotransferases. ICP is caused by impaired biliary lipid secretion, in which endogenous steroids may play a key role. Although ICP is benign for the pregnant woman, it may be harmful for the fetus. We evaluated the differences between maternal circulating steroids measured by RIA (17-hydroxypregnenolone and its sulfate, 17-hydroxyprogesterone, and cortisol) and GC-MS (additional steroids), hepatic aminotransferases and bilirubin in women with ICP (n = 15, total bile acids (TBA) >8 μM) and corresponding controls (n = 17). An age-adjusted linear model, receiver-operating characteristics (ROC), and multivariate regression (a method of orthogonal projections to latent structure, OPLS) were used for data evaluation. While aminotransferases, conjugates of pregnanediols, 17-hydroxypregnenolone and 5β-androstane-3α,17β-diol were higher in ICP patients, 20α-dihydropregnenolone, 16α-hydroxy-steroids, sulfated 17-oxo-C19-steroids, and 5β-reduced steroids were lower. The OPLS model including steroids measured by GC-MS and RIA showed 93.3% sensitivity and 100% specificity, while the model including steroids measured by GC-MS in a single sample aliquot showed 93.3% sensitivity and 94.1% specificity. A composite index including ratios of sulfated 3α/β-hydroxy-5α/β-androstane-17-ones to conjugated 5α/β-pregnane-3α/β, 20α-diols discriminated with 93.3% specificity and 81.3% sensitivity (ROC analysis). These new data demonstrating altered steroidogenesis in ICP patients offer more detailed pathophysiological insights into the role of steroids in the development of ICP.

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.

Prognostic and mechanistic potential of progesterone sulfates in intrahepatic cholestasis of pregnancy and pruritus gravidarum

A challenge in obstetrics is to distinguish pathological symptoms from those associated with normal changes of pregnancy, typified by the need to differentiate whether gestational pruritus of the skin is an early symptom of intrahepatic cholestasis of pregnancy (ICP) or due to benign pruritus gravidarum. ICP is characterized by raised serum bile acids and complicated by spontaneous preterm labor and stillbirth. A biomarker for ICP would be invaluable for early diagnosis and treatment and to enable its differentiation from other maternal diseases. Three progesterone sulfate compounds, whose concentrations have not previously been studied, were newly synthesized and assayed in the serum of three groups of ICP patients and found to be significantly higher in ICP at 9-15 weeks of gestation and prior to symptom onset (group 1 cases/samples: ICP n = 35/80, uncomplicated pregnancy = 29/100), demonstrating that all three progesterone sulfates are prognostic for ICP. Concentrations of progesterone sulfates were associated with itch severity and, in combination with autotaxin, distinguished pregnant women with itch that would subsequently develop ICP from pruritus gravidarum (group 2: ICP n = 41, pruritus gravidarum n = 14). In a third group of first-trimester samples all progesterone sulfates were significantly elevated in serum from low-risk asymptomatic women who subsequently developed ICP (ICP/uncomplicated pregnancy n = 54/51). Finally, we show mechanistically that progesterone sulfates mediate itch by evoking a Tgr5-dependent scratch response in mice.

CONCLUSION

Our discovery that sulfated progesterone metabolites are a prognostic indicator for ICP will help predict onset of ICP and distinguish it from benign pruritus gravidarum, enabling targeted obstetric care to a high-risk population. Delineation of a progesterone sulfate-TGR5 pruritus axis identifies a therapeutic target for itch management in ICP.

Pregnancy and liver disease

Pregnancy associated liver diseases affect up to 3% of pregnant women and are the most frequent cause of liver dysfunction in pregnancy. When severe, they are associated with significant morbidity and mortality for both mother and infant. A rapid evaluation to distinguish them from non-pregnancy related liver dysfunction is essential, in order to facilitate appropriate management. Liver disease unrelated to pregnancy can present de novo in pregnancy, or pregnancy can occur in women with preexisting liver pathology (Table 1). Research and subsequent advances in medical care have resulted in improved but still not satisfactory maternal and fetal outcomes. In this review we provide an overview of the liver diseases specific to the pregnant state and an update on their pathogenesis, treatment and outcomes. The risks of pregnancy in women with pre-existent liver pathology is detailed and recent advances in our understanding of specific risks and outcomes are discussed.

Pregnancy course in patients with intrahepatic cholestasis of pregnancy treated with very low doses of ursodeoxycholic acid

OBJECTIVE

Ursodeoxycholic acid (UDCA) has been proposed as the optimal pharmacological treatment for intrahepatic cholestasis of pregnancy (ICP). The lowest effective dosage of UDCA in women with ICP has not been established. The objective is to determine the risk of adverse pregnancy outcomes resulting from ICP and to measure changes in liver function parameters and pruritus severity in ICP patients treated with low doses of UDCA.

MATERIAL AND METHODS

ICP was diagnosed in 203 patients on the basis of pruritus and elevated liver biochemical parameters. Patients with total bile acids (TBA) ≥ 10 μmol/l (n = 157) received UDCA (300-450 mg/day; 4-6 mg/kg/day) until delivery. Maternal and fetal outcomes of women with ICP were compared with 100 patients without cholestasis. Patients with ICP were hospitalized for treatment and fetal surveillance.

RESULTS

There was no correlation between fetal and neonatal complication rates in ICP patients and biochemical markers of cholestasis. Significant declines in serum TBA (p = 0.003), bilirubin concentration (p = 0.026) and aminotransferase activity (p < 0.001) were observed during treatment with low doses of UDCA. Moreover, severity of pruritus was ameliorated during the 2 weeks of therapy (p = 0.037). A total of 17 patients (10.9%) did not respond to treatment.

CONCLUSIONS

UDCA at low doses improved biochemical markers and clinical symptoms in almost 90% of ICP patients.

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 ursodeoxycholic acid treatment on the altered progesterone and bile acid homeostasis in the mother-placenta-foetus trio during cholestasis of pregnancy

AIM

Intrahepatic cholestasis of pregnancy (ICP) is characterized by pruritus and elevated bile acid concentrations in maternal serum. This is accompanied by an enhanced risk of intra-uterine and perinatal complications. High concentrations of sulphated progesterone metabolites (PMS) have been suggested to be involved in the multifactorial aetiopathogenesis of ICP. The aim of this study was to investigate further the mechanism accounting for the beneficial effect of oral administration of ursodeoxycholic acid (UDCA), which is the standard treatment, regarding bile acid and PMS homeostasis in the mother-placenta-foetus trio.

METHOD

Using HPLC-MS/MS bile acids and PMS were determined in maternal and foetal serum and placenta. The expression of ABC proteins in placenta was determined by real time quantitative PCR (RT-QPCR) and immunofluorescence.

RESULTS

In ICP, markedly increased concentrations of bile acids (tauroconjugates > glycoconjugates >> unconjugated), progesterone and PMS in placenta and maternal serum were accompanied by enhanced concentrations in foetal serum of bile acids, but not of PMS. UDCA treatment reduced bile acid accumulation in the mother-placenta-foetus trio, but had no significant effect on progesterone and PMS concentrations. ABCG2 mRNA abundance was increased in placentas from ICP patients vs. controls and remained stable following UDCA treatment, despite an apparent further increase in ABCG2.

CONCLUSION

UDCA administration partially reduces ICP-induced bile acid accumulation in mothers and foetuses despite the lack of effect on concentrations of progesterone and PMS in maternal serum. Up-regulation of placental ABCG2 may play an important role in protecting the foetus from high concentrations of bile acids and PMS during ICP.

Progesterone metabolites as farnesoid X receptor inhibitors

Sulfated progesterone metabolites rise 100-fold in the third trimester of human pregnancy and have been shown to be elevated further in the gestational disorder intrahepatic cholestasis of pregnancy (ICP). Typical concentrations of progesterone sulfates range from 1 to 10 µmol/L in an uncomplicated pregnancy and rise to approximately 40 µmol/L in ICP. At this level they can influence bile acid and lipid metabolism. Studies using human and rodent specimens have shown that sulfated metabolites of progesterone competitively inhibit bile acid homeostasis pathways by functioning as partial agonists of farnesoid X receptor (FXR). This explains the loss of induction of FXR target genes in ICP, and may explain susceptibility to hypercholanaemia and dyslipidaemia in the second half of human pregnancy. Furthermore, progesterone sulfates are competitive inhibitors of biliary influx (NTCP) and efflux (BSEP) transport proteins, actions likely to further exacerbate hypercholanaemia and cholestasis.

Advances in understanding and treating liver diseases during pregnancy: A review

Liver disease in pregnancy is rare but pregnancy-related liver diseases may cause threat to fetal and maternal survival. It includes pre-eclampsia; eclampsia; haemolysis, elevated liver enzymes, and low platelets syndrome; acute fatty liver of pregnancy; hyperemesis gravidarum; and intrahepatic cholestasis of pregnancy. Recent basic researches have shown the various etiologies involved in this disease entity. With these advances, rapid diagnosis is essential for severe cases since the decision of immediate delivery is important for maternal and fetal survival. The other therapeutic options have also been shown in recent reports based on the clinical trials and cooperation and information sharing between hepatologist and gynecologist is important for timely therapeutic intervention. Therefore, correct understandings of diseases and differential diagnosis from the pre-existing and co-incidental liver diseases during the pregnancy will help to achieve better prognosis. Therefore, here we review and summarized recent advances in understanding the etiologies, clinical courses and management of liver disease in pregnancy. This information will contribute to physicians for diagnosis of disease and optimum management of patients.

Nuclear bile acid signaling through the farnesoid X receptor

Bile acids (BAs) are amphipathic molecules produced from cholesterol by the liver. Expelled from the gallbladder upon meal ingestion, BAs serve as fat solubilizers in the intestine. BAs are reabsorbed in the ileum and return via the portal vein to the liver where, together with nutrients, they provide signals to coordinate metabolic responses. BAs act on energy and metabolic homeostasis through the activation of membrane and nuclear receptors, among which the nuclear receptor farnesoid X receptor (FXR) is an important regulator of several metabolic pathways. Highly expressed in the liver and the small intestine, FXR contributes to BA effects on metabolism, inflammation and cell cycle control. The pharmacological modulation of its activity has emerged as a potential therapeutic strategy for liver and metabolic diseases. This review highlights recent advances regarding the mechanisms by which the BA sensor FXR contributes to global signaling effects of BAs, and how FXR activity may be regulated by nutrient-sensitive signaling pathways.

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.

Genetic variations of bile salt transporters

Bile salt transporters directly or indirectly influence biological processes through physicochemical or signalling properties of bile salts. The coordinated action of uptake and efflux transporters in polarized epithelial cells of the liver, biliary tree, small intestine and kidney determine bile salt concentrations in different compartments of the body. Genetic variations of bile salt transporters lead to clinical relevant phenotypes of varying severity ranging from a predisposition for drug-induced liver injury to rapidly progressing end-stage liver disease. This review focuses on the impact of genetic variations of bile salt transporters including BSEP, NTCP, ASBT and OSTα/β and discusses approaches for transporter analysis.

Rifampicin in the treatment of severe intrahepatic cholestasis of pregnancy

OBJECTIVE

To describe the use of combined ursodeoxycholic acid (UDCA) and rifampicin treatment in intrahepatic cholestasis of pregnancy (ICP).

STUDY DESIGN

A questionnaire survey of 27 women with 28 affected pregnancies identified via the UK and International Obstetric Medicine forum. The clinical case notes of women with ICP treated with combined UDCA and rifampicin therapy were reviewed, and data regarding maternal and perinatal outcomes extracted.

RESULTS

Serum bile acids remained high whilst taking UDCA as monotherapy. In 14 pregnancies (54%) serum bile acids decreased following the introduction of rifampicin. In 10 pregnancies (38%), there was a 50% reduction in serum bile acids. There were no adverse effects reported with either drug.

CONCLUSIONS

This is the first report of the use of rifampicin in ICP. The data suggest that combined treatment with UDCA and rifampicin is an effective way of treating women with severe ICP who do not respond to treatment with UDCA alone.

Management of pruritus in chronic liver disease

Background. There continues to be uncertainty on the ideal treatment of pruritus in chronic liver disease. The aim of this study was to gather the latest information on the evidence-based management of pruritus in chronic liver disease. Methodology. A literature search for pruritus in chronic liver disease was conducted using Pubmed and Embase database systems using the MeSH terms “pruritus,” “chronic liver disease,” “cholestatic liver disease,” and “treatment.” Results. The current understanding of the pathophysiology of pruritus is described in addition to detailing research into contemporary treatment options of the condition. These medical treatments range from bile salts, rifampicin, and opioid receptor antagonists to antihistamines. Conclusion. The burden of pruritus in liver disease patients persists and, although it is a common symptom, it can be difficult to manage. In recent years there has been greater study into the etiology and treatment of the condition. Nonetheless, pruritus remains poorly understood and many patients continue to suffer, reiterating the need for further research to improve our understanding of the etiology and treatment for the condition.

Jaundice associated pruritis: A review of pathophysiology and treatment

To review the underlying pathophysiology and currently available treatments for pruritis associated with jaundice. English language literature was reviewed using MEDLINE, PubMed, EMBASE and clinicaltrials.gov for papers and trails addressing the pathophysiology and potential treatments for pruritis associated with jaundice. Recent advances in the understanding of the peripheral anatomy of itch transmission have defined a histamine stimulated pathway and a cowhage stimulated pathway with sensation conveyed centrally via the contralateral spinothalamic tract. Centrally, cowhage and histamine stimulated neurons terminate widely within the thalamus and sensorimotor cortex. The causative factors for itch in jaundice have not been clarified although endogenous opioids, serotonin, steroid and lysophosphatidic acid all play a role. Current guidelines for the treatment of itching in jaundice recommend initial management with biliary drainage where possible and medical management with ursodeoxycholic acid, followed by cholestyramine, rifampicin, naltrexone and sertraline. Other than biliary drainage no single treatment has proved universally effective. Pruritis associated with jaundice is a common but poorly understood condition for which biliary drainage is the most effective therapy. Pharmacological therapy has advanced but remains variably effective.

The metabolic profile of intrahepatic cholestasis of pregnancy is associated with impaired glucose tolerance, dyslipidemia, and increased fetal growth

OBJECTIVE

Quantification of changes in glucose and lipid concentrations in women with intrahepatic cholestasis of pregnancy (ICP) and uncomplicated pregnancy and study of their influence on fetal growth.

RESEARCH DESIGN AND METHODS

A prospective study comparing metabolic outcomes in cholestastic and uncomplicated singleton pregnancies was undertaken at two university hospitals in the U.K. and U.S. from 2011-2014. A total of 26 women with ICP and 27 control pregnancies with no prior history of gestational diabetes mellitus were recruited from outpatient antenatal services and followed until delivery. Alterations in glucose, incretins, cholesterol, and triglycerides were studied using a continuous glucose monitoring (CGM) system and/or a standard glucose tolerance test (GTT) in conjunction with GLP-1 and a fasting lipid profile. Fetal growth was quantified using adjusted birth centiles.

RESULTS

Maternal blood glucose concentrations were significantly increased in ICP during ambulatory CGM (P < 0.005) and following a GTT (P < 0.005). ICP is characterized by increased fasting triglycerides (P < 0.005) and reduced HDL cholesterol (P < 0.005), similar to changes observed in metabolic syndrome. The offspring of mothers with ICP had significantly larger customized birth weight centiles, adjusted for ethnicity, sex, and gestational age (P < 0.005).

CONCLUSIONS

ICP is associated with impaired glucose tolerance, dyslipidemia, and increased fetal growth. These findings may have implications regarding the future health of affected offspring.

Cholesterol cholelithiasis in pregnant women: pathogenesis, prevention and treatment

Epidemiological and clinical studies have found that gallstone prevalence is twice as high in women as in men at all ages in every population studied. Hormonal changes occurring during pregnancy put women at higher risk. The incidence rates of biliary sludge (a precursor to gallstones) and gallstones are up to 30 and 12%, respectively, during pregnancy and postpartum, and 1-3% of pregnant women undergo cholecystectomy due to clinical symptoms or complications within the first year postpartum. Increased estrogen levels during pregnancy induce significant metabolic changes in the hepatobiliary system, including the formation of cholesterol-supersaturated bile and sluggish gallbladder motility, two factors enhancing cholelithogenesis. The therapeutic approaches are conservative during pregnancy because of the controversial frequency of biliary disorders. In the majority of pregnant women, biliary sludge and gallstones tend to dissolve spontaneously after parturition. In some situations, however, the conditions persist and require costly therapeutic interventions. When necessary, invasive procedures such as laparoscopic cholecystectomy are relatively well tolerated, preferably during the second trimester of pregnancy or postpartum. Although laparoscopic operation is recommended for its safety, the use of drugs such as ursodeoxycholic acid (UDCA) and the novel lipid-lowering compound, ezetimibe would also be considered. In this paper, we systematically review the incidence and natural history of pregnancy-related biliary sludge and gallstone formation and carefully discuss the molecular mechanisms underlying the lithogenic effect of estrogen on gallstone formation during pregnancy. We also summarize recent progress in the necessary strategies recommended for the prevention and the treatment of gallstones in pregnant women.

Successful management of severe intrahepatic cholestasis of pregnancy: report of a first Japanese case

BACKGROUND

Intrahepatic cholestasis of pregnancy (ICP) is a cholestasis condition caused by elevated levels of serum bile acids that mainly occurs in the third trimester of pregnancy. Maternal symptoms include pruritus; elevation of transaminases, biliary enzymes, and bilirubin levels; and abnormal liver function tests. Fetal symptoms include spontaneous preterm labor, fetal distress, and intrauterine death. It is more prevalent in the Caucasians and is rarely found in Asian countries, including Japan. The etiology of ICP has been reported as involving various factors such as, environmental factors, hormone balance, and genetic components. The genetic factors include single-nucleotide polymorphisms (SNPs) in the genes of canalicular transporters, including ABCB4 and ABCB11. It has also been reported that the combination of these SNPs induces severe cholestasis and liver dysfunction.

CASE PRESENTATION

Here, we report for the first time a 24-year Japanese case of severe ICP diagnosed by typical symptoms, serum biochemical analysis, and treated with the administration of ursodeoxycholic acid which improved cholestasis and liver injury and prevented fetal death. The sequence analysis showed SNPs reported their association with ICP in the ABCB11 (rs2287622, V444A) and ABCB4 (rs1202283, N168N) loci.

CONCLUSION

The risk of ICP has been reported to be population-specific, and it is rare in the Japanese population. Our case was successfully treated with ursodeoxycholic acid and the genetic sequence analysis has supported the diagnosis. Because genetic variation in ABCB4 and ABCB11 has also been reported in the Japanese population, we need to be aware of potential ICP cases in pregnant Japanese women although further studies are necessary.