Is a leaky gut involved in the pathogenesis of intrahepatic cholestasis of pregnancy?

Foetal gluten immunogenic peptides during pregnancy: a new determinant on the coeliac exposome

BACKGROUND

The increasing incidence of coeliac disease is leading to a growing interest in active search for associated factors, even the intrauterine and early life. The exposome approach to disease encompasses a life course perspective from conception onwards has recently been highlighted. Knowledge of early exposure to gluten immunogenic peptides (GIP) in utero could challenge the chronology of early prenatal tolerance or inflammation, rather than after the infant's solid diet after birth.

METHODS

We developed an accurate and specific immunoassay to detect GIP in amniotic fluid (AF) and studied their accumulates, excretion dynamics and foetal exposure resulting from AF swallowing. One hundred twenty-five pregnant women with different gluten diets and gestational ages were recruited.

RESULTS

GIP were detectable in AF from at least the 16th gestational week in gluten-consuming women. Although no significant differences in GIP levels were observed during gestation, amniotic GIP late pregnancy was not altered by maternal fasting, suggesting closed-loop entailing foetal swallowing of GIP-containing AF and subsequent excretion via the foetal kidneys.

CONCLUSIONS

The study shows evidence, for the first time, of the foetal exposure to gluten immunogenic peptides and establishes a positive correlation with maternal gluten intake. The results obtained point to a novel physiological concept as they describe a plausible closed-loop circuit entailing foetal swallowing of GIP contained in AF and its subsequent excretion through the foetal kidneys. The study adds important new information to understanding the coeliac exposome.

Maternal consumption and perinatal exposure to non-nutritive sweeteners: should we be concerned?

The context for this review is the rapid increase in the use of non-nutritive sweeteners (NNSs) instead of sugar in foods and beverages, a situation so prevalent in some countries that consumers are finding it increasingly challenging to access foods without NNSs. The benefits of consuming NNSs on obesity and diabetes are now being questioned, and studies have shown that they may exert physiological activities, sometimes independently of sweet taste receptor stimulation. Few studies, limited mainly to North American and European countries, have described the consumption of NNSs by pregnant or lactating women and infants. Most focus on beverages rather than foods, but all agree that consumption levels have increased dramatically. Although some studies report a negative impact of NNSs on the risk of preterm birth, increased birth weight and decreased gestational age, the level of evidence is low. Several studies have also reported increased weight gain in infancy, associated with maternal NNS intake. Interestingly, several NNSs have been detected in amniotic fluid and breast milk, usually (but not always) at concentrations below their established detection limit in humans. Unfortunately, the impact of chronic exposure of the fetus/infant to low levels of multiple NNSs is unknown. In conclusion, there is a stark contrast between the galloping increase in the consumption of NNSs and the small number of studies evaluating their impact in at-risk groups such as pregnant and lactating women and infants. Clearly, more studies are needed, especially in Latin America and Asia, to fill these gaps and update recommendations.

Calculus Bovis Sativus alleviates estrogen cholestasis-induced gut and liver injury in rats by regulating inflammation, oxidative stress, apoptosis, and bile acid profiles

ETHNOPHARMACOLOGICAL RELEVANCE

Natural Calculus Bovis (NCB) is a traditional Chinese medicine used for anti-inflammation, treating fever, pain, sedation, and recovering hepatobiliary function. Calculus Bovis Sativus (CBS), produced from in vitro artificial cultivation by bioengineering techniques, acts as an ideal substitute for NCB when treating various diseases.

AIM OF THE STUDY

Gut-liver injury is an important pathological feature of several cholestatic liver diseases, including estrogen-induced cholestasis (EIC). The strong link between cholestatic liver injury and intestinal damage emphasizes the need of considering gut-liver integrity during treatment. The purpose of this study is to look into the pharmacological activities of CBS on EIC-induced gut and liver damage.

MATERIALS AND METHODS

EIC-induced cholestatic rats were given oral gavage daily for five days with or without CBS (150 mg/kg). The liver/body weight, serum biochemistry, and tissue histopathology were then evaluated. Quantitative real-time PCR, Western blot analyses, and immunofluorescence were used to determine the gene expression associated with pathological alterations of the liver and intestine in EIC-induced cholestatic rats. Bile acid profiles within enterohepatic circulation were detected by liquid chromatography-mass spectrometry.

RESULTS

CBS significantly reduced relative liver weight, restored serum biochemistry levels, and improved the hepatic and intestinal pathological damage in EIC model rats. CBS reduced EIC-induced hepatic inflammation by inactivation of the NF-κB signaling and inhibition of TNFα, IL-1β, and IL-6 expression. CBS alleviated EIC-induced hepatic and intestinal oxidative stress by regulating Nrf2-GCLM/GCLC and Nrf2-HO-1 pathways, respectively. CBS treatment upregulated Bcl-2 and downregulated Bax and cleaved caspase3 to improve EIC-induced hepatic and intestinal cell apoptosis. Additionally, CBS reversed the disorders of bile acid profiles in the enterohepatic circulation by reducing bile acid accumulation in the liver and plasma and increasing bile excretion and intestinal reabsorption of bile acids.

CONCLUSION

CBS alleviates EIC-induced hepatic and intestinal injury through regulating inflammation, oxidative stress, apoptosis, and bile acid profiles. These results suggest that CBS or drugs targeting the gut-liver axis may be effective therapeutic agents for cholestasis.

Distribution of endotoxin in maternal and fetal body with intrahepatic cholestasis of pregnancy and its association with adverse fetal outcome

BACKGROUND

Intrahepatic cholestasis of pregnancy is a pregnancy-specific liver disease. In this study, we sought to explore the distribution of lipopolysaccharide in the maternal body, and its effect on the fetal body in the intrahepatic cholestasis of pregnancy mice. It provides a new sight for the clinical treatment of women with intrahepatic cholestasis of pregnancy.

METHODS

The serum levels of lipopolysaccharide and lipopolysaccharide binding protein in women with intrahepatic cholestasis of pregnancy were analyzed. To assess the association between lipopolysaccharide levels and adverse fetal outcomes, ursodeoxycholic acid, resveratrol, and phosphatidylinositol-3-kinase inhibitor were employed in intrahepatic cholestasis of pregnancy mice, and we studied the fluorescence intensity and distribution of lipopolysaccharide in mice with intrahepatic cholestasis of pregnancy.

RESULTS

Our data indicated significantly elevated levels of lipopolysaccharide and lipopolysaccharide binding protein in women with intrahepatic cholestasis of pregnancy. In vivo fluorescence imaging revealed that the intensity of lipopolysaccharide in mice with intrahepatic cholestasis of pregnancy was higher than that in the control group, and decreased after ursodeoxycholic and resveratrol treatment. The fluorescence intensity analysis indicated that lipopolysaccharide levels in maternal liver, placenta, fetal brain and fetal liver were significantly higher in the intrahepatic cholestasis pregnancy mice group than in the control group.

CONCLUSIONS

This study provided evidence of endotoxin distribution in maternal liver, placenta, fetal liver and fetal brain in mice with intrahepatic cholestasis of pregnancy. Ursodeoxycholic acid and resveratrol treatment effectively reduced lipopolysaccharide levels in pregnant mice with intrahepatic cholestasis of pregnancy.

Interactive effects of ambient air pollution and sunshine duration on the risk of intrahepatic cholestasis of pregnancy

INTRODUCTION

While the associations among ambient pollutants and various pregnancy complications are well documented, the effect of ambient pollutants on intrahepatic cholestasis of pregnancy (ICP) has not been examined. This study aimed to explore the effects of ambient pollutants and sunshine duration on ICP.

METHODS

The study enrolled 169,971 pregnant women who delivered between 2015 and 2020 in two hospitals. The associations between ICP and exposure to ambient pollutants and sunshine duration, averaged throughout different periods (including the 3 months before conception, 1st trimester and 2nd trimester), were estimated using a generalized linear model. The interaction effects of ambient pollutants and sunshine duration on ICP were estimated.

RESULTS

The fitted curves for ICP incidence were similar to the temporal trends of PM_2.5, PM₁₀, SO₂, CO and NO₂ but not that of O₃. The risk of ICP was significantly elevated following a 10-μg/m³ increase in PM_2.5 (aOR [adjusted odds ratio] = 1.057, 95% CI [confidence interval]: 1.017-1.099) and PM₁₀ (aOR = 1.043, 95% CI: 1.013-1.074) and a 1-h decrease in sunshine duration (aOR = 1.039, 95% CI: 1.011-1.068) during the 3 months before conception. In the second trimester, a 1-μg/m³ increase in the concentration of SO₂ was associated with an increased risk of ICP (aOR = 1.011, 95% CI: 1.001-1.021). Increased concentrations of PM_2.5 and PM₁₀ had interactive effects with reduced sunshine duration during the 3 months before conception on increasing the risk of ICP.

CONCLUSIONS

Exposure to PM_2.5 and PM₁₀ during the 3 months before conception and exposure to SO₂ in the second trimester were associated with an increased ICP risk. Reduced sunshine duration had an interactive effect with increased concentrations of PM_2.5 and PM₁₀ during the 3 months before conception on the occurrence of ICP.

Zonulin levels in complicated pregnancy: a systematic review and meta-analysis

Zonulin is a novel biomarker of intestinal permeability. The existing data suggest that upregulation of zonulin might be linked to systemic inflammation and pregnancy complications. A systematic search was performed in medical electronic databases to identify eligible studies that reported circulating zonulin levels in complicated pregnancies compared to controls. Eight studies with 1196 serum samples of pregnant women were included in the systematic review. Meta-analysis on four studies revealed a significant increase in serum zonulin in women with Gestational diabetes mellitus (GDM) compared to healthy controls (Cohen's d = 2.06; 95% Confidence Interval (CI): 0.15, 3.98). By pooling four studies that investigated zonulin levels in Hypertensive disorders of pregnancy (HDP), higher zonulin concentrations were found in cases, while the difference was not significant (Cohen's d = 0.86; 95% CI: -0.04, 1.75). Current evidence suggests that higher levels of zonulin during pregnancy seem to be associated with inflammation-related complications, including GDM and HDP.Impact StatementWhat is already known on this subject? Increased zonulin levels are considered as a marker of intestinal hyper-permeability. Upregulation of zonulin and concurrent systemic inflammation, are known to be associated with some pregnancy complications.What do the results of this study add? We performed a meta-analysis to evaluate changes in serum zonulin levels in pregnancies complicated with Gestational diabetes mellitus (GDM), Hypertensive disorders of pregnancy (HDP), and Intrahepatic cholestasis of pregnancy (ICP). According to our results, zonulin levels were significantly higher in complicated pregnancies than in normal pregnancies, particularly for GDM.What are the implications of these findings for clinical practice and/or further research? Our findings revealed a probable association between increased zonulin levels and inflammation-related complications during pregnancy. Moreover, zonulin could serve as a reliable diagnostic clinical biomarker to identify (or predict) complications during pregnancy. Further studies are needed to examine the clinical accuracy of zonulin for detecting pregnancy-related complications.

First encounters of the microbial kind: perinatal factors direct infant gut microbiome establishment

The human gut microbiome harbors a diverse range of microbes that play a fundamental role in the health and well-being of their host. The early-life microbiome has a major influence on human development and long-term health. Perinatal factors such as maternal nutrition, antibiotic use, gestational age and mode of delivery influence the initial colonization, development, and function of the neonatal gut microbiome. The perturbed early-life gut microbiome predisposes infants to diseases in early and later life. Understanding how perinatal factors guide and shape the composition of the early-life microbiome is essential to improving infant health. The following review provides a synopsis of perinatal factors with the most decisive influences on initial microbial colonization of the infant gut.

Inclusion of Soluble Fiber During Gestation Regulates Gut Microbiota, Improves Bile Acid Homeostasis, and Enhances the Reproductive Performance of Sows

Interaction between the dietary fiber and the gut microbes can regulate host bile acid metabolism. This study sought to explore the effects of guar gum combined with pregelatinized waxy maize starch (GCW) in a gestation diet on reproductive performance, gut microbiota composition, and bile acid homeostasis of sows. A total of 61 large white sows were randomly grouped into the control (n = 33) and 2% GCW (n = 28) groups during gestation. GCW diet increased birth-weight of piglets, and decreased the percentage of intrauterine growth restriction (IUGR) piglets. In addition, dietary GCW reduced gut microbial diversity and modulated gut microbial composition in sows on day 109 of gestation. The relative abundance of bile salt hydrolase (BSH) gene-encoding bacteria, Lactobacillus and Bacteroides decreased after GCW administration, whereas no significant difference was observed in the fecal level of total glycine-conjugated and taurine-conjugated bile acids between the two groups. Dietary GCW increased the relative abundance of Ruminococcaceae (one of few taxa comprising 7α-dehydroxylating bacteria), which was associated with elevated fecal deoxycholic acid (DCA) in the GCW group. GCW administration lowered the concentrations of plasma total bile acid (TBA) and 7α-hydroxy-4-cholesten-3-one (C4) (reflecting lower hepatic bile acid synthesis) at day 90 and day 109 of gestation compared with the control diet. Furthermore, the levels of plasma glycoursodeoxycholic acid (GUDCA), tauroursodeoxycholic acid (TUDCA) and glycohyocholic acid (GHCA) were lower in the GCW group compared with the control group. Spearman correlation analysis showed alterations in the composition of the gut microbiota by GCW treatment was associated with improved bile acid homeostasis and reproductive performance of sows. In conclusion, GCW-induced improves bile acid homeostasis during gestation which may enhance reproductive performance of sows.

How Do Serum Zonulin Levels Change in Gestational Diabetes Mellitus, Pregnancy Cholestasis, and the Coexistence of Both Diseases?

We investigated the question of how serum zonulin levels change in intrahepatic cholestasis of pregnancy (ICP) and gestational diabetes mellitus (GDM) and, in the case of the coexistence of ICP and GDM, evaluated the eventual increase in zonulin plasmatic levels. Participants were enrolled for the study between 25 February 2021 and 20 August 2021. The prospective case-control study included: group 1 of 95 pregnant women diagnosed with ICP; group 2 of 110 pregnant women diagnosed with GDM; group 3 of 16 women diagnosed with both GDM and ICP; group 4 of 136 healthy pregnant women as the control group. The groups were compared in terms of age, body mass index (BMI), gravidity, parity, gestational week of delivery, plasma zonulin levels, delivery type, birth weight, first- and fifth-minute APGAR scores, newborn intensive care unit (NICU) admission, and meconium staining of amniotic fluid parameters. The results suggested that the plasma zonulin levels of ICP (group 1), GDM (group 2), and GDM with ICP (group 3) patients were higher than those of the healthy pregnant women of group 4 (p < 0.001). Among the patient groups, the highest median plasma zonulin levels were found in group 3 (110.33 ng/mL). Zonulin levels were also associated with the severity of ICP and adverse pregnancy outcomes. High serum zonulin levels were related to GDM, ICP, and adverse perinatal outcomes. The coexistence of GDM and ICP led to higher serum zonulin concentrations.

Estrogen cholestasis induces gut and liver injury in rats involving in activating PI3K/Akt and MAPK signaling pathways

BACKGROUNDS

Estrogen and its metabolites often lead to intrahepatic cholestasis in susceptible women with pregnancy, administration of oral contraceptives and postmenopausal hormone replacement therapy. Recently, dysfunction of the gut-liver axis has been suggested to play a pivotal role in the progression of cholestasis, but details about estrogen cholestasis (EC)-induced gut and liver injury are still largely unknown. This study aims to gain insight into EC-induced gut and liver injury and cell signaling implicated.

METHODS

Male rats were exposed to 5 and 10 mg/kg of 17α-ethinylestradiol via subcutaneous injection for 5 successive days to simulate human EC.

RESULTS

By detection of these estrogen cholestatic rats, we found that EC induced inflammation in the liver but not in the intestine through activating NF-κB signaling pathway. EC strongly induced oxidative stress in both the liver and intestine, and activated the hepatic Nrf2/Gclm/Gclc pathway and the intestinal Nrf2/Ho-1 pathway, respectively, for adaptively regulating oxidative stress. EC increased cell apoptosis in both the liver and intestine. Additionally, EC elevated phosphorylation of Akt, ERK1/2, and p38 in the liver and increased phosphorylation of p38 in the intestine.

CONCLUSIONS

EC induces liver inflammation, both gut and liver oxidative stress and apoptosis, involving in activating PI3K/Akt and MAPK signaling pathways. Investigation of EC-induced gut and liver injury contributes to the development of new potential therapeutic strategies.

IL-13 as Target to Reduce Cholestasis and Dysbiosis in Abcb4 Knockout Mice

The Th2 cytokine IL-13 is involved in biliary epithelial injury and liver fibrosis in patients as well as in animal models. The aim of this study was to investigate IL-13 as a therapeutic target during short term and chronic intrahepatic cholestasis in an Abcb4-knockout mouse model (Abcb4^-/-). Lack of IL-13 protected Abcb4^-/- mice transiently from cholestasis. This decrease in serum bile acids was accompanied by an enhanced excretion of bile acids and a normalization of fecal bile acid composition. In Abcb4^-/-/IL-13^-/- double knockout mice, bacterial translocation to the liver was significantly reduced and the intestinal microbiome resembled the commensal composition in wild type animals. In addition, 52-week-old Abcb4^-/-IL-13^-/- mice showed significantly reduced hepatic fibrosis. Abcb4^-/- mice devoid of IL-13 transiently improved cholestasis and converted the composition of the gut microbiota towards healthy conditions. This highlights IL-13 as a potential therapeutic target in biliary diseases.

Maternal diet during pregnancy and intestinal markers are associated with early gut microbiota

BACKGROUND

Diet has an important role in host-microbiome interplay, which may result in intestinal permeability changes and physiopathological effects at a systemic level. Despite the importance of maternal microbiota as the main contributor to the initial microbial seeding, little is known about the effects of maternal diet during pregnancy on maternal-neonatal microbiota.

OBJECTIVES

This study aimed at ascertaining the possible associations between maternal dietary intake during pregnancy and neonatal microbiota at birth and to evaluate the relationship with maternal intestinal markers.

METHODS

In a nested cross-sectional study in the longitudinal MAMI cohort, maternal-neonatal microbiota profiling at birth (n = 73) was assessed by 16S rRNA gene sequencing. Maternal intestinal markers as zonulin, intestinal alkaline phosphatase (IAP) activity and faecal calprotectin were measured in faeces. Furthermore, maternal-neonatal clinical and anthropometric data, as well as maternal nutrient intake during pregnancy obtained by FFQ questionnaires, were collected.

RESULTS

Maternal diet is associated with both maternal and neonatal microbiota at the time of birth, in a delivery mode-dependent manner. The existing link between maternal diet, intestinal makers and neonatal gut microbiota would be mainly influenced by the intake of saturated (SFA) and monounsaturated fatty acids (MUFA). Members of Firmicutes in the neonatal microbiota were positively associated with maternal fat intake, especially SFA and MUFA, and negatively correlated to fibre, proteins from vegetable sources and vitamins.

CONCLUSIONS

Maternal diet during pregnancy, mainly fat intake (SFA and MUFA), was related to intestinal markers, thus likely shifting the microbial transmission to the neonate and priming the neonatal microbial profile with potential health outcomes.

CLINICAL TRIAL REGISTRY

NCT03552939.

Total serum bile acids or serum bile acid profile, or both, for the diagnosis of intrahepatic cholestasis of pregnancy

BACKGROUND

Intrahepatic cholestasis of pregnancy is a pregnancy-specific liver disorder, possibly associated with an increased risk of severe fetal adverse events. Total serum bile acids (TSBA) concentration, alone or in combination with serum aminotransferases, have been the most often used biomarkers for the diagnosis of intrahepatic cholestasis of pregnancy in clinical practice. Serum bile acid profile, composed of primary or secondary, conjugated or non-conjugated bile acids, may provide more specific disease information.

OBJECTIVES

To assess and compare, independently or in combination, the diagnostic accuracy of total serum bile acids or serum bile acids profile, or both, for the diagnosis of intrahepatic cholestasis of pregnancy in pregnant women, presenting with pruritus. To define the optimal cut-off values for components of serum bile acid profile; to investigate possible sources of heterogeneity.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Hepato-Biliary Group Diagnostic Test Accuracy Studies Register, the Cochrane Library, MEDLINE Ovid, Embase Ovid, Science Citation Index Expanded, Conference Proceedings Citation Index - Science, BIOSIS, CINAHL, two Chinese databases (CKNI, VIP), Latin American and Caribbean Health Sciences Literature (LILACS), Scientific Electronic Library Online (SciELO), Evidence Search: Health and Social Care by the National Institute for Health and Care Excellence (NICE), the World Health Organization (WHO) Reproductive Health Library (RHL), and the Turning Research into Practice database (TRIP). The most recent date of search was 6 May 2019. We identified additional references by handsearching the references of articles, meta-analyses, and evidence-based guidelines retrieved from the computerised databases, on-line trial registries, and grey literature through OpenSIGLE, National Technical Information Service (NTIS), ProQuest Dissertations & Thesis Database, and Index to Theses in Great Britain and Ireland.

SELECTION CRITERIA

Prospective or retrospective diagnostic case-control or cross-sectional studies, irrespective of publication date, format, and language, which evaluated the diagnostic accuracy of total serum bile acids (TSBA) or components of serum bile acid profile for the diagnosis of intrahepatic cholestasis of pregnancy in pregnant women of any age or ethnicity, in any clinical setting, symptomatic for pruritus.

DATA COLLECTION AND ANALYSIS

We selected studies by reading titles, abstracts, or full texts, and assessing their fulfilment of our inclusion criteria. We emailed primary authors to request missing data or individual participant data. Having extracted data from each included study, we built the two-by-two tables for each primary study and for all the index tests considered. We estimated sensitivity and specificity with their 95% confidence intervals (CI). We presented data in coupled forest plots, showing sensitivities and specificities of each study, and we plotted the studies in the Receiver Operating Characteristic (ROC) space. We performed meta-analyses adopting the hierarchical summary ROC model (HSROC) or the bivariate model to meta-analyse the data. We made indirect comparisons of the considered index tests by adding the index tests as covariates to the bivariate or HSROC models. We performed heterogeneity analysis and sensitivity analysis on studies assessing TSBA accuracy. We used Review Manager 5 (RevMan 5) and SAS statistical software, release 9.4 (SAS Institute Inc., Cary, NC, USA), to perform all statistical analyses. We used QUADAS-2 domains to assess the risk of bias of the included studies.

MAIN RESULTS

Our search yielded 5073 references, but at the end of our selection process, only 16 studies fulfilled the review inclusion criteria. Nine of these provided individual participant data. We analysed only data concerning TSBA, cholic acid (CA), glycocholic acid (GCA), chenodeoxycholic acid (CDCA), and CA/CDCA because the remaining planned index tests were assessed in few studies. Only one study had low risk of bias in all four QUADAS-2 domains. The most biased domains were the patient sampling and the reference standard domains. When considering all studies with a cut-off of 10 μmol/L, TSBA overall sensitivity ranged from 0.72 to 0.98 and specificity ranged from 0.81 to 0.97. After a sensitivity analysis excluding case-control studies, TSBA sensitivity ranged from 0.48 to 0.66 and specificity from 0.52 to 0.99. After a sensitivity analysis excluding studies in which TSBA was part of the reference standard, TSBA sensitivity ranged from 0.49 to 0.65 and specificity from 0.53 to 0.99. We found the estimates of the overall accuracy for some serum bile acid components (CA, GCA, CDCA, and CA/CDCA) to be imprecise, with the CI for sensitivity and specificity very wide or impossible to calculate. Indirect comparisons between serum bile acid profile components and TSBA were not statistically significant. None of the heterogeneity analysis performed was statistically significant, except for the timing of assessment of TSBA (onset of symptoms, peak value among multiple assessments, delivery) but without clinically relevant results. We could not analyse the diagnostic accuracy of combinations of index tests because none of the included studies carried them out, and because of the small number of included studies.

AUTHORS' CONCLUSIONS

The overall high risk of bias, the existing concern regarding applicability of the results in clinical practice, and the great heterogeneity of the results in the included studies prevents us from making recommendations and reaching definitive conclusions at the present time. Thus, we do not find any compelling evidence to recommend or refute the routine use of any of these tests in clinical practice. So far, the diagnostic accuracy of TSBA for intrahepatic cholestasis of pregnancy might have been overestimated. There were too few studies to permit a precise estimate of the accuracy of serum bile acid profile components. Further primary clinical research is mandatory. We need both further phase II and phase III diagnostic studies.

The impact of probiotics and n-3 long-chain polyunsaturated fatty acids on intestinal permeability in pregnancy: a randomised clinical trial

A disruption in intestinal barrier integrity may predispose individuals to metabolic aberrations, particularly during the vulnerable period of pregnancy. We investigated whether intestinal permeability, as measured by serum zonulin concentration, changes over the duration of pregnancy and whether this change is reflected in lipopolysaccharide (LPS) activity. Second, we tested in a randomised double-blind placebo controlled clinical trial the impact of consuming dietary probiotics and/or long chain polyunsaturated fatty acid (LC-PUFA) supplements in lowering serum zonulin concentration and LPS activity. The probiotic supplement was a combination of two bacteria, Bifidobacterium animalis ssp. lactis 420 and Lactobacillus rhamnosus HN001. This study included 200 overweight pregnant women participating in an on-going study; participants were randomised to consume either (1) probiotics, (2) LC-PUFA, (3) probiotics and LC-PUFA, or (4) placebo for each supplement. Blood samples were obtained at early, the baseline, and late pregnancy (mean 14 and 35 weeks of gestation, respectively). Serum zonulin concentration increased from early (mean (standard deviation): 62.7 (12.9) ng/ml) to late pregnancy by 5.3 (95%CI 3.7-6.9) ng/ml, and LPS activity increased from (0.16 (0.04) EU/ml) by 0.04 (95%CI 0.03-0.05) EU/ml. No differences among the intervention groups were detected in the change from early to late pregnancy in serum zonulin concentration (P=0.8) or LPS activity (P=0.2). The change in serum zonulin concentration during the pregnancy was associated with the weeks of follow up (r=0.25, P<0.001). Serum LPS activity was correlated with higher maternal weight gain (r=0.19, P=0.008). As a conclusion, intestinal permeability increased with the progression of pregnancy in overweight and obese women and was reflected in LPS activity. No efficacy of supplementation with probiotics and/or LC-PUFA was demonstrated in pregnancy-induced changes in serum zonulin concentration or LPS activity.

Incorporating the gut microbiota into models of human and non-human primate ecology and evolution

The mammalian gut is home to a diverse community of microbes. Advances in technology over the past two decades have allowed us to examine this community, the gut microbiota, in more detail, revealing a wide range of influences on host nutrition, health, and behavior. These host-gut microbe interactions appear to shape host plasticity and fitness in a variety of contexts, and therefore represent a key factor missing from existing models of human and non-human primate ecology and evolution. However, current studies of the gut microbiota tend to include limited contextual data or are clinical, making it difficult to directly test broad anthropological hypotheses. Here, I review what is known about the animal gut microbiota and provide examples of how gut microbiota research can be integrated into the study of human and non-human primate ecology and evolution with targeted data collection. Specifically, I examine how the gut microbiota may impact primate diet, energetics, disease resistance, and cognition. While gut microbiota research is proliferating rapidly, especially in the context of humans, there remain important gaps in our understanding of host-gut microbe interactions that will require an anthropological perspective to fill. Likewise, gut microbiota research will be an important tool for filling remaining gaps in anthropological research.

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.

Early life events influence whole-of-life metabolic health via gut microflora and gut permeability

The capacity of our gut microbial communities to maintain a stable and balanced state, termed 'resilience', in spite of perturbations is vital to our achieving and maintaining optimal health. A loss of microbial resilience is observed in a number of diseases including obesity, diabetes and metabolic syndrome. There are large gaps in our understanding of why an individual's co-evolved microflora consortium fail to develop resilience thereby establishing a trajectory towards poor metabolic health. This review examines the connections between the developing gut microbiota and intestinal barrier function in the neonate, infant and during the first years of life. We propose that the effects of early life events on the gut microflora and permeability, whilst it is in a dynamic and vulnerable state, are fundamental in shaping the microbial consortia's resilience and that it is the maintenance of resilience that is pivotal for metabolic health throughout life. We review the literature supporting this concept suggesting new potential research directions aimed at developing a greater understanding of the longitudinal effects of the gut microflora on metabolic health and potential interventions to recalibrate the 'at risk' infant gut microflora in the direction of enhanced metabolic health.

Promoter DNA methylation of farnesoid X receptor and pregnane X receptor modulates the intrahepatic cholestasis of pregnancy phenotype

The intrahepatic cholestasis of pregnancy (ICP) is a multifactorial liver disorder which pathogenesis involves the interplay among abnormal bile acid (BA) levels, sex hormones, environmental factors, and genetic susceptibility. The dynamic nature of ICP that usually resolves soon after delivery suggests the possibility that its pathobiology is under epigenetic modulation. We explored the status of white blood peripheral cells-DNA methylation of CpG-enriched sites at the promoter of targeted genes (FXR/NR1H4, PXR/NR1I2, NR1I3, ESR1, and ABCC2) in a sample of 88 ICP patients and 173 healthy pregnant women in the third trimester of their pregnancies. CpG dinucleotides at the gene promoter of nuclear receptors subfamily 1 members and ABCC2 transporter were highly methylated during healthy pregnancy. We observed significant differences at the distal (−1890) and proximal promoter (−358) CpG sites of the FXR/NR1H4 and at the distal PXR/NR1I2 (−1224) promoter, which were consistently less methylated in ICP cases when compared with controls. In addition, we observed that methylation at FXR/NR1H4-1890 and PXR/NR1I2-1224 promoter sites was highly and positively correlated with BA profiling, particularly, conjugated BAs. Conversely, methylation level at the proximal FXR/NR1H4-358 CpG site was significantly and negatively correlated with the primary cholic and secondary deoxycholic acid. In vitro exploration showed that epiallopregnanolone sulfate, a reported FXR inhibitor, regulates the transcriptional activity of FXR/NR1H4 but seems to be not involved in the methylation changes. In conclusion, the identification of epigenetic marks in target genes provides a basis for the understanding of adverse liver-related pregnancy outcomes, including ICP.

Intestinal mucosal permeability of children with cefaclor-associated serum sickness-like reactions

Although the serum sickness-like reaction (SSLR) in children after the administration of cefaclor has long been recognized, the exact mechanism of cefaclor-associated SSLR remains unclear. This study aims to investigate the association between intestinal mucosal permeability and cefaclor-associated SSLR in children. A total of 82 pediatric patients with upper respiratory tract infection following the cefaclor therapy was divided into cefaclor-associated SSLR positive group and negative group based on the presence or absence of SSLR after taking cefaclor, and 30 healthy volunteers served as control group. Urinary lactulose/mannitol (L/M) ratios and serum diamine oxidase (DAO) levels were determined in all cases on days 7, 9, 11, 13, and 15 after oral administration of cefaclor. The children in the control group were given the same measurements after enrollment in this study. From days 7 to 13, the urinary L/M ratio of children with cefaclor SSLR gradually increased and reached to the highest level of 0.38 ± 0.14 on day 13. Compared with the cefaclor-associated SSLR negative group and control group, urinary L/M ratios increased significantly in the cefaclor SSLR positive group on days 7, 9, 11, 13, and 15 after taking cefaclor, and serum levels of DAO following the treatment of cefaclor increased significantly in children with cefaclor SSLR on days 9, 11, 13, and 15. No significant difference in urinary L/M ratios and serum levels of DAO between SSLR negative group and control group through the entire experiment was observed. In conclusion, administration of cefaclor may induce SSLR in children by increasing the intestinal mucosal permeability and/or affecting the integrity of the intestinal mucosa. Determinations of urinary L/M ratios and serum DAO levels may be helpful for observing or predicting the occurrence of SSLR after administration of cefaclor, which will encourage physicians to proceed with extreme caution when prescribing cefaclor for pediatric patients.

Health history after intrahepatic cholestasis of pregnancy

OBJECTIVE

To establish whether intrahepatic cholestasis of pregnancy (ICP) is associated with other diseases during a woman's lifetime.

DESIGN

Prospective controlled cohort study.

SETTING

University Hospital in Finland.

POPULATION

A total of 575 women with ICP and 1374 control women, all having delivered in 1969-1988. Questionnaires were sent to 544 ICP patients and 1235 control women. Responses were received from 1178 (66.4%).

METHODS

Questionnaire survey in autumn 2010.

MAIN OUTCOME MEASURES

Perceived health, symptoms and complaints, diseases diagnosed by a doctor and use of medicines.

RESULTS

No statistically significant differences were detected in perceived health. Differences in recent symptoms and complaints were small. Diagnoses made by a doctor showed higher frequencies in the ICP group than in control women for other hepatobiliary diseases, breast cancer and hypothyreosis. Diagnosed hypertension and high cholesterol requiring medication as well as cardiac arrhythmia were less frequent in the ICP group. Women in this group used antacid medicines more often than control women.

CONCLUSIONS

There were few differences between the ICP patients and control women except for a higher frequency of later hepatobiliary disease, breast cancer and hypothyreosis. Women with a history of ICP should be screened for hypothyreosis more readily than those without. The higher frequency of breast cancer warrants further research.

Liver disease in pregnancy

This article briefly discusses gestational physiologic changes and thereafter reviews liver diseases during pregnancy, which are divided into 3 main categories. The first category includes conditions that are unique to pregnancy and generally resolve with the termination of pregnancy, the second category includes liver diseases that are not unique to the pregnant population but occur commonly or are severely affected by pregnancy, and the third category includes diseases that occur coincidentally with pregnancy and in patients with underlying chronic liver disease, with cirrhosis, or after liver transplant who become pregnant.

Pregnancy-related liver diseases

Liver diseases related to pregnancy may be associated with preeclampsia (liver dysfunction related to preeclampsia; hemolysis, elevated liver enzymes, and low platelets with or without preeclampsia [HELLP syndrome]; and acute fatty liver of pregnancy) or may not involve preeclampsia (hyperemesis gravidarum and intrahepatic cholestasis of pregnancy). Liver diseases associated with pregnancy have unique presentations, but it can be difficult differentiating these from liver diseases that occur coincidentally with pregnancy. Recently, advances have been made in the disease mechanism and intervention of pregnancy-related liver diseases. Early diagnosis and delivery remains the key element in managing the liver diseases associated with preeclampsia, but emerging data suggest that incorporating advance supportive management into current strategies can improve both maternal and fetal outcomes.

Pregnancy dermatoses: diagnosis, management, and controversies

Some aspects regarding the etiology and the nosologic classification of various pregnancy dermatoses are highly controversial. While some authors highlight the existence of premises allowing several skin disorders to be re-grouped within broader disease concepts, others underline the absence of clear, undisputed etiopathogenetic data that could support such classifications. This review exhaustively analyzes the various pregnancy dermatoses (pemphigoid gestationis, intrahepatic cholestasis of pregnancy, impetigo herpetiformis, polymorphic eruption of pregnancy, and the papular dermatoses of pregnancy [prurigo of pregnancy, pruritic folliculitis of pregnancy, and the new classification, atopic eruption of pregnancy]) in an attempt to shed light over this confusing and disputed domain, while subsequently offering an algorithmic approach to their diagnosis and management. While for pemphigus gestationis, intrahepatic cholestasis of pregnancy, and impetigo herpetiformis, specific diagnostic tests such as histopathology, immunofluorescence, or laboratory investigations will confirm the diagnosis, the identification of the other types of pregnancy dermatoses is based only on clinical criteria. In this context, the review argues for the inclusion of the whole group represented by the papular dermatoses of pregnancy within the broad spectrum of polymorphic eruption of pregnancy, separating each of these entities by focusing on their onset: early-onset polymorphic eruption of pregnancy (comprising prurigo of pregnancy, pruritic folliculitis of pregnancy, and atopic eruption of pregnancy) and late-onset polymorphic eruption of pregnancy. In light of the same practical approach guiding it, the review provides updated treatment strategies for each of these conditions.

Endotoxin and CD14 in the progression of biliary atresia

Background

Biliary atresia (BA) is a typical cholestatic neonatal disease, characterized by obliteration of intra- and/or extra-hepatic bile ducts. However, the mechanisms contributing to the pathogenesis of BA remain uncertain. Because of decreased bile flow, infectious complications and damaging endotoxemia occur frequently in patients with BA. The aim of this study was to investigate endotoxin levels in patients with BA and the relation of these levels with the expression of the endotoxin receptor, CD14.

Methods

The plasma levels of endotoxin and soluble CD14 were measured with a pyrochrome Limulus amebocyte lysate assay and enzyme-linked immunosorbent assay in patients with early-stage BA when they received the Kasai procedure (KP), in patients who were jaundice-free post-KP and followed-up at the outpatient department, in patients with late-stage BA when they received liver transplantation, and in patients with choledochal cysts. The correlation of CD14 expression with endotoxin levels in rats following common bile duct ligation was investigated.

Results

The results demonstrated a significantly higher hepatic CD14 mRNA and soluble CD14 plasma levels in patients with early-stage BA relative to those with late-stage BA. However, plasma endotoxin levels were significantly higher in both the early and late stages of BA relative to controls. In rat model, the results demonstrated that both endotoxin and CD14 levels were significantly increased in liver tissues of rats following bile duct ligation.

Conclusions

The significant increase in plasma endotoxin and soluble CD14 levels during BA implies a possible involvement of endotoxin stimulated CD14 production by hepatocytes in the early stage of BA for removal of endotoxin; whereas, endotoxin signaling likely induced liver injury and impaired soluble CD14 synthesis in the late stages of BA.

Alcoholic liver injury: Influence of gender and hormones

This article discusses several subjects pertinent to a consideration of the role of gender and hormones in alcoholic liver injury (ALI). Beginning with an overview of factors involved in the pathogenesis of ALI, we review changes in sex hormone metabolism resulting from alcohol ingestion, summarize research that points to estrogen as a cofactor in ALI, consider evidence that gut injury is linked to liver injury in the setting of alcohol, and briefly review the limited evidence regarding sex hormones and gut barrier function. In both women and female animals, most studies reveal a propensity toward greater alcohol-induced liver injury due to female gender, although exact hormonal influences are not yet understood. Thus, women and their physicians should be alert to the dangers of excess alcohol consumption and the increased potential for liver injury in females.

The influence of common gene variants of the xenobiotic receptor (PXR) in genetic susceptibility to intrahepatic cholestasis of pregnancy

BACKGROUND

The xenobiotic nuclear pregnane X receptor is implicated in many physiological pathways and diseases, including bile acid detoxification and cholestasis. Aim To estimate the contribution of common gene variants of the xenobiotic receptor (pregnane X receptor, PXR) to genetic susceptibility to intrahepatic cholestasis of pregnancy.

METHODS

A total of 101 intrahepatic cholestasis of pregnancy patients and 171 healthy pregnant women in the third trimester of their pregnancies were included. Four tag single nucleotide polymorphisms (SNPs) (rs12488820 C/T, rs2472671 C/T, rs2461823 A/G, and rs1054191 A/G) encompassing 36 kb in chromosome 3, with a minor allele frequency > or =0.10 and representing 33 polymorphic sites were genotyped. Besides these, three additional SNPs (rs3814057, rs6785049, and rs7643645) were included because they showed previous evidence of functionality.

RESULTS

Genotypic test for single SNPs showed that rs2461823 genotypes were significantly associated with intrahepatic cholestasis of pregnancy (P < 0.0069), OR per G allele: 1.44, 95% CI: 1.01-2.05, P < 0.042. The Cochran-Armitage test for trend and the allelic test showed a significant association with disease status (P < 0.04 and 0.03 respectively), G being the risk allele. A positive association between rs2461823 and ALT, AST, and bilirubin concentrations was observed. Neonate birth weight adjusted by the Capurro index was significantly associated with rs2461823 (P < 0.05); the proportion of the total variation attributed to rs2461823 genotypes was 7.8%.

CONCLUSION

Common PXR polymorphisms may contribute to the genetic susceptibility to intrahepatic cholestasis of pregnancy.

Intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific liver disorder characterized by maternal pruritus in the third trimester, raised serum bile acids and increased rates of adverse fetal outcomes. The etiology of ICP is complex and not fully understood, but it is likely to result from the cholestatic effects of reproductive hormones and their metabolites in genetically susceptible women. Equally unclear are the mechanisms by which the fetal complications occur. This article reviews the epidemiology, clinical features, diagnosis, etiology and management of ICP.

Intrahepatic cholestasis of pregnancy-current achievements and unsolved problems

Intrahepatic cholestasis of pregnancy (ICP) is the most common pregnancy-related liver disorder. Maternal effects of ICP are mild; however, there is a clear association between ICP and higher frequency of fetal distress, preterm delivery, and sudden intrauterine fetal death. The cause of ICP remains elusive, but there is evidence that mutations in genes encoding hepatobiliary transport proteins can predispose for the development of ICP. Recent data suggest that ursodeoxycholic acid is currently the most effective pharmacologic treatment, whereas obstetric management is still debated. Clinical trials are required to identify the most suitable monitoring modalities that can specifically predict poor perinatal outcome. This article aims to review current achievements and unsolved problems of ICP.

Increased intestinal endotoxin absorption during enteric nematode but not protozoal infections through a mast cell-mediated mechanism

It is known that hypersensitivity reactions in the gastrointestinal tract, which are primarily mediated by mast cells, are associated with a secretory response of the epithelium and often increased permeability to macromolecules. Studies to date have not examined the effects of hyperpermeability on the absorption of toxic substances normally present in the intestinal lumen such as bacterial LPS. In the present study, we observed that Strongyloides venezuelensis infection in mice decreases the mRNA expression of intestinal epithelial cell junctional molecules (occludin and zonula occludens 1) and increases portal endotoxin levels 4 h after intragastric administration of LPS (20 mg/kg body weight). Furthermore, an increase in the flux of immunoglobulin G into the intestinal lumen was observed 10 days postinfection (PI). An increased rate of LPS absorption was also seen in mice infected with Nippostrongylus brasiliensis on day 14 PI and rats concurrently infected with S. venezuelensis and N. brasiliensis on day 20 PI. On the other hand, infection with Eimeria vermiformis and Eimeria pragensis was not observed to enhance LPS absorption 4 h after intragastric administration of LPS (20 mg/kg body weight), although E. vermiformis infection did inhibit the epithelial cell mRNA expression of zonula occludens 1, but not occludin, on day 9 PI, resulting in a reduced immunoglobulin G flux than that produced by S. venezuelensis infection. Our results suggest that mastocytosis accompanying intestinal nematode infection increases the intestinal absorption of LPS into the portal circulation by suppressing the expression of tight junction molecules.

Pregnancy-associated liver disorders

Liver disorders associated with pregnancy include hyperemesis gravidarum (HG), intrahepatic cholestasis of pregnancy (ICP), preeclampsia, syndrome of hemolysis, elevated liver enzymes and low platelets (HELLP), and acute fatty liver of pregnancy (AFLP). These conditions are relatively common and unique to pregnancy and are more likely to occur at certain terms of gestation specific to each condition. They can be associated with significant maternal and fetal morbidity and mortality. Although managing such patients may be very challenging, spontaneous resolution of the disease occurs shortly after termination of the pregnancy, usually without hepatic sequellae. Early diagnosis and timely treatment is a key to therapeutic success. This article explores the clinical features, pathophysiology, and management of these disorders.

Altered intestinal permeability in patients with primary fibromyalgia and in patients with complex regional pain syndrome

OBJECTIVES

The pain intensity of patients with FM has recently been reported to be correlated with the degree of small intestinal bacterial overgrowth (SIBO). SIBO is often associated with an increased intestinal permeability (IP). Increased IP, if shown in FM, may have pathogenetic relevance because it leads to the exposure of immune cells to luminal antigens and consequent immune modulation. It is currently unknown whether IP is altered in FM. We therefore examined the IP in a group of patients with primary FM and in two control groups, healthy volunteers and patients with an unrelated chronic pain syndrome, complex regional pain syndrome (CRPS). We hypothesized that patients with FM, but not volunteers or those patients with CRPS, would have altered IP.

METHODS

Both gastroduodenal and small IP were assessed using an established three-sugar test, where urinary disaccharide excretion reflecting intestinal uptake was measured using HPLC.

RESULTS

Forty patients with primary FM, 57 age- and sex-matched volunteers and 17 patients with CRPS were enrolled in this study. In the FM group, 13 patients had raised gastroduodenal permeability and 15 patients had raised small intestinal permeability, but only one volunteer had increased gastroduodenal permeability (P < 0.0001, chi-square test for the three groups). The IP values were significantly increased in the patient groups (P < 0.0003 for all comparisons, one-way analysis of variance).

CONCLUSIONS

The IPs in primary FM and, unexpectedly, CRPS are increased. This study should stimulate further research to determine the implication of altered IP in the disease pathophysiology of FM and CRPS.

Molecular pathogenesis of intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) occurs mainly in the third trimester and is characterised by pruritus and elevated serum bile acid levels. ICP is associated with an increased perinatal risk and higher rates of foetal morbidity and mortality. Although the pathogenesis of this disease is unknown, a genetic hypersensitivity to female hormones (oestrogen and/or progesterone) or their metabolites is thought to impair bile secretory function. Recent data suggest that mutations or polymorphisms of genes expressing hepatobiliary transport proteins or their nuclear regulators may contribute to the development and/or severity of ICP. Unidentified environmental factors may also influence pathogenesis of the disease. This review summarises current knowledge on the potential mechanisms involved in ICP at the molecular level.

Pregnancy and liver disease

Although liver disease does not occur frequently during pregnancy, when it does, it can cause significant morbidity and mortality for both fetus and mother. Recent advances in molecular genetics have provided some insight into the pathogenesis of diseases such as intrahepatic cholestasis of pregnancy (IHCP) and acute fatty liver of pregnancy. Newer studies linking serum bile acid levels with fetal outcome support the importance of this marker in IHCP. Randomized trials with ursodeoxycholic acid have shown promising results in reducing maternal symptoms and serum bile acid levels in IHCP. Although further studies must be performed, early strategies aimed at reducing viral loads in mothers may reduce perinatal transmission of hepatitis B.

Liver diseases unique to pregnancy

Liver injury and dysfunction in a pregnant woman may be caused by intrinsic features of the pregnancy itself, disorders that are coincidental with pregnancy or pre-existing liver disease that is exacerbated by pregnancy. The clinical setting, gestational age and standard liver biochemistry testing are useful tools in helping to establish a diagnosis. Prompt recognition of the signs of liver disease in pregnant patients leads to timely management and may save the life of both mother and baby. This review summarises the incidence, risk factors, pathogenesis, clinical presentation, diagnosis, treatment and outcome of those liver diseases unique to pregnancy.

Cholestasis and cholestatic syndromes

PURPOSE OF REVIEW

This review focuses on the recent advances in cholestatic liver diseases. While there is an emphasis placed on translational and treatment-focused studies, basic science studies with the greatest impact on the field are also covered.

RECENT FINDINGS

Highlights include new discoveries for the role of the farsenoid X receptor and sodium-dependent taurocholate cotransporting polypeptide; new insights into the pathogenesis of progressive familial intrahepatic cholestasis type 1, biliary atresia, intrahepatic cholestasis of pregnancy, and primary biliary cirrhosis; new information for assessing prognosis in biliary atresia and primary biliary cirrhosis; and important clinical trials in intrahepatic cholestasis of pregnancy, primary biliary cirrhosis and primary sclerosing cholangitis.

SUMMARY

The studies of 2006 have furthered our understanding of cholestasis and cholestatic syndromes. While we continue to add to our knowledge of pathogenesis and treatment for many of these diseases, much work remains.