Serum Bile Acid Concentrations Research Articles

Impact of Genotype, Serum Bile Acids, and Surgical Biliary Diversion on Native Liver Survival in FIC1 Deficiency.

Background and AimsMutations in ATPase phospholipid transporting 8B1 (ATP8B1) can lead to familial intrahepatic cholestasis type 1 (FIC1) deficiency, or progressive familial intrahepatic cholestasis type 1. The rarity of FIC1 deficiency has largely prevented a detailed analysis of its natural history, effects of predicted protein truncating mutations (PPTMs), and possible associations of serum bile acid (sBA) concentrations and surgical biliary diversion (SBD) with long‐term outcome. We aimed to provide insights by using the largest genetically defined cohort of patients with FIC1 deficiency to date.Approach and ResultsThis multicenter, combined retrospective and prospective study included 130 patients with compound heterozygous or homozygous predicted pathogenic ATP8B1 variants. Patients were categorized according to the number of PPTMs (i.e., splice site, frameshift due to deletion or insertion, nonsense, duplication), FIC1‐A (n = 67; no PPTMs), FIC1‐B (n = 29; one PPTM), or FIC1‐C (n = 34; two PPTMs). Survival analysis showed an overall native liver survival (NLS) of 44% at age 18 years. NLS was comparable among FIC1‐A, FIC1‐B, and FIC1‐C (% NLS at age 10 years: 67%, 41%, and 59%, respectively; P = 0.12), despite FIC1‐C undergoing SBD less often (% SBD at age 10 years: 65%, 57%, and 45%, respectively; P = 0.03). sBAs at presentation were negatively associated with NLS (NLS at age 10 years, sBAs < 194 µmol/L: 49% vs. sBAs ≥ 194 µmol/L: 15%; P = 0.03). SBD decreased sBAs (230 [125‐282] to 74 [11‐177] μmol/L; P = 0.005). SBD (HR 0.55, 95% CI 0.28‐1.03, P = 0.06) and post‐SBD sBA concentrations < 65 μmol/L (P = 0.05) tended to be associated with improved NLS.ConclusionsLess than half of patients with FIC1 deficiency reach adulthood with native liver. The number of PPTMs did not associate with the natural history or prognosis of FIC1 deficiency. sBA concentrations at initial presentation and after SBD provide limited prognostic information on long‐term NLS.

Conjugated C-6 hydroxylated bile acids in serum relate to human metabolic health and gut Clostridia species

Knowledge about in vivo effects of human circulating C-6 hydroxylated bile acids (BAs), also called muricholic acids, is sparse. It is unsettled if the gut microbiome might contribute to their biosynthesis. Here, we measured a range of serum BAs and related them to markers of human metabolic health and the gut microbiome. We examined 283 non-obese and obese Danish adults from the MetaHit study. Fasting concentrations of serum BAs were quantified using ultra-performance liquid chromatography-tandem mass-spectrometry. The gut microbiome was characterized with shotgun metagenomic sequencing and genome-scale metabolic modeling. We find that tauro- and glycohyocholic acid correlated inversely with body mass index (P = 4.1e-03, P = 1.9e-05, respectively), waist circumference (P = 0.017, P = 1.1e-04, respectively), body fat percentage (P = 2.5e-03, P = 2.3e-06, respectively), insulin resistance (P = 0.051, P = 4.6e-4, respectively), fasting concentrations of triglycerides (P = 0.06, P = 9.2e-4, respectively) and leptin (P = 0.067, P = 9.2e-4). Tauro- and glycohyocholic acids, and tauro-a-muricholic acid were directly linked with a distinct gut microbial community primarily composed of Clostridia species (P = 0.037, P = 0.013, P = 0.027, respectively). We conclude that serum conjugated C-6-hydroxylated BAs associate with measures of human metabolic health and gut communities of Clostridia species. The findings merit preclinical interventions and human feasibility studies to explore the therapeutic potential of these BAs in obesity and type 2 diabetes.

Congenital gallbladder agenesis in a 9-month-old Bull Terrier

Congenital gallbladder agenesis is an extremely rare disorder, which has, to the best of our knowledge, only been reported in seventeen dogs (mainly in Japan). In almost all of these cases, gallbladder agenesis or hypoplasia was detected in small dogs. In this report, we present a case of gallbladder agenesis in a 9-month-old intact female Bull Terrier. The clinical signs included diarrhoea, sporadic vomiting, apathy and decreased appetite. The serum biochemistry revealed an increased liver enzyme activity, an increased concentration of serum bile acids and mild hyperbilirubinaemia. A diagnostic laparotomy demonstrated the lack of a gallbladder and dilation of the common bile duct, which was misinterpreted as the gallbladder in the ultrasonographic examination. The histological examination of the liver revealed degenerative changes in the hepatocytes with glycogen accumulation and some necrotic hepatocytes. The therapy included a low protein diet, fluids, silymarin and ursodeoxycholic acid. After nine weeks of therapy, the dog was in good condition, the diarrhoea and vomiting ceased, and the liver function parameters, such as the AST and GLDH activities, and the concentration of bile acids had decreased to reference intervals.

Bile acid synthesis, modulation, and dementia: A metabolomic, transcriptomic, and pharmacoepidemiologic study.

While Alzheimer disease (AD) and vascular dementia (VaD) may be accelerated by hypercholesterolemia, the mechanisms underlying this association are unclear. We tested whether dysregulation of cholesterol catabolism, through its conversion to primary bile acids (BAs), was associated with dementia pathogenesis. We used a 3-step study design to examine the role of the primary BAs, cholic acid (CA), and chenodeoxycholic acid (CDCA) as well as their principal biosynthetic precursor, 7α-hydroxycholesterol (7α-OHC), in dementia. In Step 1, we tested whether serum markers of cholesterol catabolism were associated with brain amyloid accumulation, white matter lesions (WMLs), and brain atrophy. In Step 2, we tested whether exposure to bile acid sequestrants (BAS) was associated with risk of dementia. In Step 3, we examined plausible mechanisms underlying these findings by testing whether brain levels of primary BAs and gene expression of their principal receptors are altered in AD. Step 1: We assayed serum concentrations CA, CDCA, and 7α-OHC and used linear regression and mixed effects models to test their associations with brain amyloid accumulation (N = 141), WMLs, and brain atrophy (N = 134) in the Baltimore Longitudinal Study of Aging (BLSA). The BLSA is an ongoing, community-based cohort study that began in 1958. Participants in the BLSA neuroimaging sample were approximately 46% male with a mean age of 76 years; longitudinal analyses included an average of 2.5 follow-up magnetic resonance imaging (MRI) visits. We used the Alzheimer's Disease Neuroimaging Initiative (ADNI) (N = 1,666) to validate longitudinal neuroimaging results in BLSA. ADNI is an ongoing, community-based cohort study that began in 2003. Participants were approximately 55% male with a mean age of 74 years; longitudinal analyses included an average of 5.2 follow-up MRI visits. Lower serum concentrations of 7α-OHC, CA, and CDCA were associated with higher brain amyloid deposition (p = 0.041), faster WML accumulation (p = 0.050), and faster brain atrophy mainly (false discovery rate [FDR] p = <0.001-0.013) in males in BLSA. In ADNI, we found a modest sex-specific effect indicating that lower serum concentrations of CA and CDCA were associated with faster brain atrophy (FDR p = 0.049) in males.Step 2: In the Clinical Practice Research Datalink (CPRD) dataset, covering >4 million registrants from general practice clinics in the United Kingdom, we tested whether patients using BAS (BAS users; 3,208 with ≥2 prescriptions), which reduce circulating BAs and increase cholesterol catabolism, had altered dementia risk compared to those on non-statin lipid-modifying therapies (LMT users; 23,483 with ≥2 prescriptions). Patients in the study (BAS/LMT) were approximately 34%/38% male and with a mean age of 65/68 years; follow-up time was 4.7/5.7 years. We found that BAS use was not significantly associated with risk of all-cause dementia (hazard ratio (HR) = 1.03, 95% confidence interval (CI) = 0.72-1.46, p = 0.88) or its subtypes. We found a significant difference between the risk of VaD in males compared to females (p = 0.040) and a significant dose-response relationship between BAS use and risk of VaD (p-trend = 0.045) in males.Step 3: We assayed brain tissue concentrations of CA and CDCA comparing AD and control (CON) samples in the BLSA autopsy cohort (N = 29). Participants in the BLSA autopsy cohort (AD/CON) were approximately 50%/77% male with a mean age of 87/82 years. We analyzed single-cell RNA sequencing (scRNA-Seq) data to compare brain BA receptor gene expression between AD and CON samples from the Religious Orders Study and Memory and Aging Project (ROSMAP) cohort (N = 46). ROSMAP is an ongoing, community-based cohort study that began in 1994. Participants (AD/CON) were approximately 56%/36% male with a mean age of 85/85 years. In BLSA, we found that CA and CDCA were detectable in postmortem brain tissue samples and were marginally higher in AD samples compared to CON. In ROSMAP, we found sex-specific differences in altered neuronal gene expression of BA receptors in AD. Study limitations include the small sample sizes in the BLSA cohort and likely inaccuracies in the clinical diagnosis of dementia subtypes in primary care settings. We combined targeted metabolomics in serum and amyloid positron emission tomography (PET) and MRI of the brain with pharmacoepidemiologic analysis to implicate dysregulation of cholesterol catabolism in dementia pathogenesis. We observed that lower serum BA concentration mainly in males is associated with neuroimaging markers of dementia, and pharmacological lowering of BA levels may be associated with higher risk of VaD in males. We hypothesize that dysregulation of BA signaling pathways in the brain may represent a plausible biologic mechanism underlying these results. Together, our observations suggest a novel mechanism relating abnormalities in cholesterol catabolism to risk of dementia.

Gut-restricted apical sodium-dependent bile acid transporter inhibitor attenuates alcohol-induced liver steatosis and injury in mice.

Recent studies have shown that human and experimental alcohol-related liver disease (ALD) is robustly associated with dysregulation of bile acid homeostasis, which may in turn modulate disease severity. Pharmacological agents targeting bile acid metabolism and signaling may be potential therapeutics for ALD. The potential beneficial effects of a gut-restricted apical sodium-dependent bile acid transporter (ASBT) inhibitor were studied in a chronic-plus-binge ALD mouse model. Blocking intestinal bile acid reabsorption by the gut-restricted ASBT inhibitor GSK2330672 attenuated hepatic steatosis and liver injury in a chronic-plus-binge ALD mouse model. Alcohol feeding is associated with intestinal bile acid accumulation but paradoxically impaired ileal farnesoid×receptor (FXR) function, and repressed hepatic cholesterol 7α-hydrolase (CYP7A1) expression despite decreased hepatic small heterodimer partner (SHP) and ileal fibroblast growth factor 15 (FGF15) expression. ASBT inhibitor treatment decreased intestinal bile acid accumulation and increased hepatic CYP7A1 expression, but further decreased ileal FXR activity. Alcohol feeding induces serum bile acid concentration that strongly correlates with a liver injury marker. However, alcohol-induced serum bile acid elevation is not due to intrahepatic bile acid accumulation but is strongly and positively associated with hepatic multidrug resistance-associated protein 3 (MRP4) and MRP4 induction but poorly associated with sodium-taurocholate cotransporting peptide (NTCP) expression. ASBT inhibitor treatment decreases serum bile acid concentration without affecting hepatocyte basolateral bile acid uptake and efflux transporters. ASBT inhibitor treatment corrects alcohol-induced bile acid dysregulation and attenuates liver injury in experimental ALD.

Resting and postprandial serum bile acid concentrations in dogs with liver disease.

BackgroundSerum bile acids (SBAs) are frequently measured in dogs. However, there is limited data comparing SBAs in different liver diseases diagnosed according to standardized histological criteria.ObjectivesTo compare resting and postprandial SBAs, and determine their sensitivity and specificity, for various liver diseases in dogs.AnimalsThree hundred and forty‐one client‐owned dogs with suspected liver disease that had a liver biopsy and SBAs measured.MethodsMulticenter retrospective study. Cases were classified according to standardized histological criteria. The sensitivity and specificity of resting and postprandial SBAs for the diagnosis of each liver disease, and all liver diseases combined, were calculated.ResultsThe median resting SBAs were highest in dogs with cirrhosis (98.8 μmol/L; range, 6‐135) and congenital circulatory anomalies (CCa; 79.45 μmol/L; 0.3‐705). The highest median postprandial concentrations were found in CCa (126 μmol/L; 0‐726) and chronic hepatitis (CH; 54.3 μmol/L; 0‐260). Using the cut‐off value of 10 μmol/L, the highest sensitivities of resting SBAs were recorded in dogs with CCa (87.5%; 95% confidence interval, 76.8‐94.4) and CH (81.1%; 71.5‐88.6). The sensitivities of postprandial SBAs were the highest in cholangitis (100%; 47.8‐100.0) and CCa (91.1%; 78.8‐97.5). The specificities of resting and postprandial SBAs for all diseases were 49.3% (37.6‐61.1) and 29.7% (15.9‐47.0), respectively.Conclusions and Clinical ImportancePostprandial SBAs are more sensitive but less specific than resting SBAs for the diagnosis of liver disease. There were dogs in all categories of liver disease with resting SBAs <10 and >90 μmol/L. Therefore, careful interpretation of both normal and elevated values is required.

Metabolic Activation of Retrorsine may Disrupt Bile Acid Homeostasis in Mice through the Nrf2 Pathway

The hepatotoxic pyrrolizidine alkaloids (PAs) were reported to increase bile acid (BA) levels in the rat. However, it is still unclear whether the production of highly reactive dehydropyrrolizidine through CYP450s is directly relevant to BA changes. To further explore the mechanism by which metabolic activation of PAs induced BA changes, the effect of impaired or enhanced metabolic activation on the BA profiling and BA-related synthesis and to investigate transport genes, and explore the involvement of the Nrf2 pathway. Blood and liver samples were collected after intragastrical administration of 35 mg/kg retrorsine or saline for seven days in wild-type (WT) and Nrf2 KO mice. CYP450 inhibitor, 1-aminobenzotriazole (ABT), or gammaglutamylcysteine synthetase inhibitor, L-buthionine-sulfoximine (BSO) were employed in WT mice. Retrorsineinduced hepatotoxicity was evaluated by a biochemical method and H&E staining method. Serum BAs were quantified by high-performance liquid chromatography/triple quadrupole mass spectrometry. Blood pyrrole-protein adducts were semi quantified by high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry. The gene and protein expression of BA-related transporters and enzymes in the liver were measured by a quantitative real-time PCR method and western blotting method. The BA concentrations in serum were increased in the retrorsine-treated WT mice, along with the upregulation of BA transporters, Ostβ, Mrp3, Mrp4, and Mrp2. When ABT was co-administered, the altered BA levels and Mrp4 mRNA and protein levels were reversed, accompanied by a 50% reduction of 6,7-dihydro-7-hydroxy-1- hydroxymethyl-5H-pyrrolizine (DHP) formation. When BSO was co-administered, serum BAs were not further increased, but Ostβ, Mrp3, Mrp4 mRNA, and Mrp4 protein levels continuously increased. The induction of Mrp4 by retrorsine among the tested BA transporters was the only one that was abolished or enhanced in the presence of ABT or BSO. The Nrf2 protein levels in the nucleus increased in the retrorsine-treated WT mice, which were remarkably repressed by co-administration of ABT and enhanced by co-administration of BSO. In Nrf2 KO mice receiving retrorsine, the bile acids and the mRNA and protein levels of Mrp2, Mrp3, Mrp4, and Ostβ were hardly changed, indicating the direct role of Nrf2 in retrorsine-induced BA changes in WT mice. The activation of Nrf2 translocation by forming the reactive metabolite of PAs induced the expressions of BA transporters and changed serum BA levels. Mrp4 was a sensitive biomarker for the perturbation of redox status caused by the formation of dehydropyrrolizidine.

Intrahepatic cholestasis of pregnancy

Die Schwangerschaftscholestase („intrahepatic cholestasis of pregnancy“, ICP) ist die häufigste schwangerschaftsspezifische Lebererkrankung. Das Leitsymptom Juckreiz sowie eine begleitende Serumkonzentrationserhöhung von Gallensäuren und/oder der Alaninaminotransferase (ALT) sind wegweisend in der Diagnosestellung. Die mütterliche Prognose ist gut. Das fetale Outcome ist abhängig von der Gallensäurenkonzentration. Die ICP ist dabei sowohl mit Frühgeburt als auch mit intrauterinem Fruchttod (IUFT) assoziiert. Dieser ist Folge einer akuten fetalen Asphyxie, nicht einer chronischen uteroplazentaren Dysfunktion. Ein prädiktives Monitoring, z. B. durch Kardiotokographie (CTG) oder Ultraschall gibt es nicht. Eine medikamentöse Therapie mit Ursodeoxycholsäure (UDCA) bessert den Juckreiz, aber beeinflusst das fetale Outcome nicht nachweislich. Eine Entbindungsindikation ist in Abhängigkeit von Gallensäurenkonzentration und Gestationsalter gegeben. In Folgeschwangerschaften besteht ein hohes Wiederholungsrisiko.

Conjugated secondary 12α-hydroxylated bile acids promote liver fibrogenesis

BackgroundSignificantly elevated serum and hepatic bile acid (BA) concentrations have been known to occur in patients with liver fibrosis. However, the roles of different BA species in liver fibrogenesis are not fully understood. MethodsWe quantitatively measured blood BA concentrations in nonalcoholic steatohepatitis (NASH) patients with liver fibrosis and healthy controls. We characterized BA composition in three mouse models induced by carbon tetrachloride (CCl4), streptozotocin-high fat diet (STZ-HFD), and long term HFD, respectively. The molecular mechanisms underlying the fibrosis-promoting effects of BAs were investigated in cell line models, a 3D co-culture system, and a Tgr5 (HSC-specific) KO mouse model. FindingsWe found that a group of conjugated 12α-hydroxylated (12α-OH) BAs, such as taurodeoxycholate (TDCA) and glycodeoxycholate (GDCA), significantly increased in NASH patients and liver fibrosis mouse models. 12α-OH BAs significantly increased HSC proliferation and protein expression of fibrosis-related markers. Administration of TDCA and GDCA directly activated HSCs and promoted liver fibrogenesis in mouse models. Blockade of BA binding to TGR5 or inhibition of ERK1/2 and p38 MAPK signaling both significantly attenuated the BA-induced fibrogenesis. Liver fibrosis was attenuated in mice with Tgr5 depletion. InterpretationIncreased hepatic concentrations of conjugated 12α-OH BAs significantly contributed to liver fibrosis via TGR5 mediated p38MAPK and ERK1/2 signaling. Strategies to antagonize TGR5 or inhibit ERK1/2 and p38 MAPK signaling may effectively prevent or reverse liver fibrosis. FundingsThis study was supported by the National Institutes of Health/National Cancer Institute Grant 1U01CA188387-01A1, the National Key Research and Development Program of China (2017YFC0906800); the State Key Program of National Natural Science Foundation (81430062); the National Natural Science Foundation of China (81974073, 81774196), China Postdoctoral Science Foundation funded project, China (2016T90381), and E-institutes of Shanghai Municipal Education Commission, China (E03008).

Amelioration of hyperglycaemia and hyperlipidaemia by adjusting the interplay between gut microbiota and bile acid metabolism: Radix Scutellariae as a case

BackgroundOur previous clinical research showed that the interaction between gut microbiota and bile acids (BAs) in patients with type 2 diabetes mellitus (T2DM) changed significantly. We hypothesized that T2DM could be improved by adjusting this interaction mediated by farnesoid X receptor (FXR). T2DM belongs to the category of “xiaoke” in traditional Chinese medicine. Radix scutellariae has the effects of clearing away heat and eliminating dampness, curing jaundice and quenching thirst and is widely used alone or in combination with other medicines for the treatment of T2DM in China and throughout Asia. Additionally, the interaction between Radix scutellariae and gut microbiota may influence its efficacy in the treatment of T2DM. PurposeThis study chose Radix scutellariae to validate that T2DM could improve by adjusting the interaction between gut microbiota and bile acid metabolism. Study design and methodsRadix scutellariae water extract (WESB) was administered to a T2DM rat model established by a high-fat diet combined with streptozotocin. The body weight and blood glucose and insulin levels were measured. The levels of serum lipids, creatinine, uric acid, albumin and total bile acid were also detected. Changes in the pathology and histology of the pancreas, liver and kidney were observed by haematoxylin-eosin staining. The 16S rRNAs of gut microbiota were sequenced, and the faecal and serum BAs were determined by liquid chromatography tandem mass spectrometry. The expression levels of BA metabolism-associated proteins in the liver and intestine were evaluated by immunoblot analysis. ResultsThe results showed that WESB improved hyperglycaemia, hyperlipaemia, and liver and kidney damage in T2DM rats. In addition, the abundances of key gut microbiota and the concentrations of certain secondary BAs in faeces and serum were restored. Moreover, there was a significant correlation between the restored gut microbiota and BAs, which might be related to the activation of liver cholesterol 7α-hydroxylase (CYP7A1) and the inhibition of FXR expression in the intestine rather than the liver. ConclusionsThis study provided new ideas for the prevention or treatment of clinical diabetes and its complications by adjusting the interaction between gut microbiota and bile acid metabolism.

Manganese and copper levels in patients with primary biliary cirrhosis and primary sclerosing cholangitis

The liver and the biliary tree form the main excretory route of manganese (Mn) and copper (Cu). Cholestasis, can lead to the accumulation of these trace elements in the organism, resulting in toxicity to the basal ganglia of the central nervous system. The aim of our study was to reveal the influence of long-term cholestasis on the Mn and Cu levels in the blood of patients with primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). We recruited patients with PBC (n = 20) and PSC (n = 32). A control group (n = 40) was also set up. We also examined serum bile acid concentrations and liver enzyme activities. We did not observe any significant differences in any of these parameters between the PBC and PSC groups. The Mn and Cu levels in the PBC and PSC patients differed significantly from the that in the control group (p < 0.0001 and p < .021, respectively). Patients in whom the laboratory cholestasis markers normalized during ursodeoxycholic acid treatment (18/52;35%) presented with significantly lower levels of Mn and Cu (p = .015 and p = .012, respectively). Ten PSC patients showed normal levels of Mn and Cu six months after liver transplantation. Fine tremors, rigidity, dysarthria, and hypomimia were reported in nine (23%), eight (20%), four (10%), and eight (20%) patients, respectively. In addition to monitoring the cholestasis levels, liver function, and Mn and Cu levels during the long-term treatment of PBC and PSC patients, it is important to also regularly monitor the occurrence and development of extrapyramidal symptoms of Parkinson’s-like syndromes.

Elobixibat, an ileal bile acid transporter inhibitor, ameliorates non-alcoholic steatohepatitis in mice.

Recent studies have suggested that several types of toxic bile acids (BAs) are involved in the pathogenesis of non-alcoholic steatohepatitis (NASH). In the present study, we aimed to determine whether elobixibat, an ileal bile acid transporter (IBAT) inhibitor, would ameliorate NASH in mice. C57BL/6N mice were fed a methionine and choline-deficient (MCD) to induce NASH or standard diet as control for 8weeks (n = 5 per group). The MCD diet-fed mice were administered elobixibat 5days a week for 4weeks by gavage (n = 5). The effects of the treatments on liver histopathology, proinflammatory cytokine concentrations, intestinal epithelial tight junctions, and the intestinal microbial composition were then assessed. In MCD-fed mice, hepatic fibrosis and inflammatory cell infiltration developed, and the serum aspartate transaminase activity and BA concentration were higher than the control. In addition, the proinflammatory cytokine concentrations were high in the liver and mesenteric lymph nodes (MLN), and the expression of intestinal epithelium tight junction proteins, claudin1, was increased. In the intestinal microbial composition, the abundance of the Lachnospiraceae and Ruminococcaeae were decreased, whereas that of the Enterobacteriaceae was increased. Treatment with elobixibat reduced the serum BA and increased the fecal BA concentration, and ameliorated the liver inflammation and fibrosis. It also reduced the expression of proinflammatory cytokines in the liver and MLNs, and transforming growth factor-β expression in the liver. Finally, elobixibat normalized intestinal tight junction protein level and the composition of the intestinal microbiota. Elobixibat ameliorates NASH-related histopathology, reduces cytokine expression, and normalizes the intestinal microbial composition in MCD-fed mice, which suggests that it may represent a promising candidate for the therapy of NASH.

Obstetric Cholestasis: A Review and Update

Obstetric cholestasis (OC) is a liver disorder that occurs in the late second and early third trimester of pregnancy characterized by pruritus with increased serum bile acids and other liver function tests. The pathophysiology of OC is still not completely understood. The symptoms and biochemical abnormality rapidly resolve after delivery. OC is associated with an increased risk of adverse obstetrical outcomes. The aetiology of obstetric cholestasis of pregnancy is poorly understood and is thought to be complicated and multifactorial. OC typically occurs in the late second trimester when the oestrogen levels are the highest in pregnancy. The most common complaint is generalized intense pruritus, which usually starts after the 30th week of pregnancy. Pruritus can be more common in the palms and soles and is typically worse at night. Other symptoms of cholestasis, such as nausea, anorexia, fatigue, right upper quadrant pain, dark urine, and pale stool, can be present. Clinical jaundice is rare but may present in 14% to 25% of patients after 1 to 4 weeks of the onset of pruritus. Some patients also complain of insomnia as a result of pruritus. Generally, physical examination is unremarkable except for scratch marks on the skin from pruritus. Pruritus is a cardinal symptom of intra-hepatic cholestasis of pregnancy (ICP) and may precede biochemical abnormalities. The diagnosis of intrahepatic cholestasis of pregnancy is via the presence of clinical symptoms pruritus in the third trimester with elevated maternal total serum bile acids and excluding other diagnoses, which can cause similar symptoms and lab abnormalities. Fasting blood samples should be used to check for the total bile salt acid level as it can become elevated in the postprandial state.&#x0D; Once the diagnosis of OC of pregnancy is confirmed, immediate treatment is necessary, and the primary goal of therapy is to decrease the risk of perinatal morbidity and mortality and to alleviate maternal symptoms. Maternal pruritus can be alleviated with use of moisturisers and oral antihistamines. Ursodeoxycholic acid (UDCA) is the drug of choice for the treatment of ICP.&#x0D; Many authors have advocated elective early delivery of women with intrahepatic cholestasis of pregnancy to reduce the risk of sudden foetal death. The Royal College of Obstetricians and Gynaecologists recommends induction of labour after 37+0 weeks of gestation. Obstetric cholestasis of pregnancy is not an indication for Caesarean delivery. Postpartum pruritus typically disappears in the first 2 to 3 days following delivery, and serum bile acid concentrations will normalize eventually. ICP is not a contraindication to breastfeeding, and mothers with a history of ICP in pregnancy can breastfeed their infants. Postpartum monitoring and follow up of bile acids and liver function tests should be done in 4-6 weeks to ensure resolution. Women with the persistent abnormality of liver function test after 6 to 8 weeks require investigation for other aetiologies.

The problem of uncertain adherence to study interventions: what can we conclude?

Intrahepatic cholestasis of pregnancy (ICP), the most common liver disease in pregnancy, is characterised by elevated bile acid concentrations and maternal pruritus, and has been associated with increased rates of stillbirth, preterm birth, and neonatal unit admission. Fetal complications have been associated with rising serum bile acids (Glantz et al, Hepatology 2004;40:467- 474) and, according to a recent individual patient data meta-analysis (Ovadia et al, The Lancet 2019;393:899-909), the risk of stillbirth increased in women with serum bile acid concentrations of 100 μmol/l or more.

Bile Acids in Dementia: Brain Amyloid, White Matter Lesions, and Atrophy

While Alzheimer’s disease (AD) and vascular dementia (VaD) may be accelerated by hypercholesterolemia, the mechanisms underlying this association is unclear. Using a novel, 3-step study design we examined the role of cholesterol catabolism in dementia by testing whether 1) the synthesis of the primary cholesterol breakdown products (bile acids (BA)) were associated with neuroimaging markers of dementia; 2) pharmacological modulation of BAs alters dementia risk; and 3) brain BA concentrations and gene expression were associated with AD. We found that higher serum concentrations of BAs are associated with lower brain amyloid deposition, slower WML accumulation, and slower brain atrophy in males. Opposite effects were observed in females. Modulation of BA levels alters risk of incident VaD in males. Altered brain BA signaling at the metabolite and gene expression levels occurs in AD. Dysregulation of peripheral cholesterol catabolism and BA synthesis may impact dementia pathogenesis through signaling pathways in the brain.

Fetal cardiac dysfunction in intrahepatic cholestasis of pregnancy is associated with elevated serum bile acid concentrations

Background & AimsIntrahepatic cholestasis of pregnancy (ICP) is associated with an increased risk of stillbirth. This study aimed to assess the relationship between bile acid concentrations and fetal cardiac dysfunction in patients with ICP who were or were not treated with ursodeoxycholic acid (UDCA).MethodsBile acid profiles and NT-proBNP, a marker of ventricular dysfunction, were assayed in umbilical venous serum from 15 controls and 76 ICP cases (36 untreated, 40 UDCA-treated). Fetal electrocardiogram traces were obtained from 43 controls and 48 ICP cases (26 untreated, 22 UDCA-treated). PR interval length and heart rate variability (HRV) parameters were measured in 2 behavioral states (quiet and active sleep).ResultsIn untreated ICP, fetal total serum bile acid (TSBA) concentrations (r = 0.49, p = 0.019), hydrophobicity index (r = 0.20, p = 0.039), glycocholate concentrations (r = 0.56, p = 0.007) and taurocholate concentrations (r = 0.44, p = 0.039) positively correlated with fetal NT-proBNP. Maternal TSBA (r = 0.40, p = 0.026) and alanine aminotransferase (r = 0.40, p = 0.046) also positively correlated with fetal NT-proBNP. There were no significant correlations between maternal or fetal serum bile acid concentrations and fetal HRV parameters or NT-proBNP concentrations in the UDCA-treated cohort. Fetal PR interval length positively correlated with maternal TSBA in untreated (r = 0.46, p = 0.027) and UDCA-treated ICP (r = 0.54, p = 0.026). Measures of HRV in active sleep and quiet sleep were significantly higher in untreated ICP cases than controls. HRV values in UDCA-treated cases did not differ from controls.ConclusionsElevated fetal and maternal serum bile acid concentrations in untreated ICP are associated with an abnormal fetal cardiac phenotype characterized by increased NT-proBNP concentration, PR interval length and HRV. UDCA treatment partially attenuates this phenotype.Lay summaryThe risk of stillbirth in intrahepatic cholestasis of pregnancy (ICP) is linked to the level of bile acids in the mother which are thought to disrupt the baby’s heart rhythm. We found that babies of women with untreated ICP have abnormally functioning hearts compared to those without ICP, and the degree of abnormality is closely linked to the level of harmful bile acids in the mother and baby’s blood. Babies of women with ICP who received treatment with the drug UDCA do not have the same level of abnormality in their hearts, suggesting that UDCA could be a beneficial treatment in some ICP cases, although further clinical trials are needed to confirm this.

Bile accelerates carcinogenic processes in pancreatic ductal adenocarcinoma cells through the overexpression of MUC4

Pancreatic cancer (PC) is one of the leading causes of mortality rate globally and is usually associated with obstructive jaundice (OJ). Up to date, there is no clear consensus on whether biliary decompression should be performed prior to surgery and how high levels of serum bile affects the outcome of PC. Therefore, our study aims were to characterise the effect of bile acids (BAs) on carcinogenic processes using pancreatic ductal adenocarcinoma (PDAC) cell lines and to investigate the underlying mechanisms. Liquid chromatography-mass spectrometry was used to determine the serum concentrations of BAs. The effects of BAs on tumour progression were investigated using different assays. Mucin expressions were studied in normal and PDAC cell lines and in human samples at gene and protein levels and results were validated with gene silencing. The levels of BAs were significantly higher in the PDAC + OJ group compared to the healthy control. Treating PDAC cells with different BAs or with human serum obtained from PDAC + OJ patients enhanced the rate of proliferation, migration, adhesion, colony forming, and the expression of MUC4. In PDAC + OJ patients, MUC4 expression was higher and the 4-year survival rate was lower compare to PDAC patients. Silencing of MUC4 decreased BAs-induced carcinogenic processes in PDAC cells. Our results show that BAs promote carcinogenic process in PDAC cells, in which the increased expression of MUC4 plays an important role. Based on these results, we assume that in PC patients, where the disease is associated with OJ, the early treatment of biliary obstruction improves life expectancy.

Ursodeoxycholic acid to reduce adverse perinatal outcomes for intrahepatic cholestasis of pregnancy: the PITCHES RCT

Background Intrahepatic cholestasis of pregnancy, characterised by maternal pruritus and raised serum bile acid concentrations, is associated with increased rates of stillbirth, preterm birth and neonatal unit admission. Ursodeoxycholic acid is widely used as a treatment, but without an adequate evidence base. Objective We aimed to evaluate whether or not ursodeoxycholic acid reduces adverse perinatal outcomes in affected women. Design Multicentre, masked, randomised, placebo-controlled, two-arm, parallel-group trial. Setting Thirty-three UK maternity units. Participants Women with intrahepatic cholestasis of pregnancy aged ≥ 18 years, between 20+0 and 40+6 weeks’ gestation with a singleton or twin pregnancy and no known lethal fetal anomaly. Interventions Women were randomly assigned (1 : 1 allocation ratio) to take ursodeoxycholic acid tablets or matched placebo tablets, at an equivalent dose of 1000 mg daily, titrated as needed. Main outcome measures The primary outcome was a composite of perinatal death (in utero fetal death after randomisation or known neonatal death up to 7 days) or preterm delivery (&lt; 37 weeks’ gestation) or neonatal unit admission for at least 4 hours (from birth until hospital discharge). Each infant was counted once within this composite. Analyses were by intention to treat. Results Between 23 December 2015 and 7 August 2018, 605 women were randomised, with 305 women allocated to the ursodeoxycholic acid arm and 300 women to the placebo arm. There was no evidence of a significant difference in the incidence of the primary outcome between the groups: 23.0% (74 out of 322 infants) in the ursodeoxycholic acid group compared with 26.7% (85 out of 318 infants) in the placebo group; adjusted risk ratio 0.85 (95% confidence interval 0.62 to 1.15). There was no evidence of a significant difference in total costs (maternal, infant and the cost of ursodeoxycholic acid) between the two trial groups. There were two serious adverse events in the ursodeoxycholic acid group and six in the placebo group. Limitations Limitations include a primary outcome event rate in the control group that was lower than that estimated for the sample size calculation, but the lack of evidence of effect in all analyses suggests that it is unlikely that the trial had insufficient power. Conclusions In this clinical trial of ursodeoxycholic acid in women with intrahepatic cholestasis of pregnancy, there is no evidence that it is effective in reducing a composite of adverse perinatal outcomes. Future work Future research should aim to elucidate the aetiology and pathophysiology of adverse perinatal outcomes, particularly stillbirth, in women with intrahepatic cholestasis of pregnancy to assist the development of an effective preventative treatment. Further exploratory analyses may identify groups of women who might respond to ursodeoxycholic acid treatment. Trial registration Current Controlled Trials ISRCTN91918806. Funding This project was funded by the Efficacy and Mechanism Evaluation (EME) Programme, a Medical Research Council and National Institute for Health Research (NIHR) partnership. This will be published in full in Efficacy and Mechanism Evaluation; Vol. 7, No. 9. See the NIHR Journals Library website for further project information.

Analytical performance and method comparison of a quantitative point-of-care immunoassay for measurement of bile acids in cats and dogs.

Point-of-care analyzers (POCAs) for quantitative assessment of bile acids (BAs) are scarce in veterinary medicine. We evaluated the Fuji Dri-Chem Immuno AU10V analyzer and v-BA test kit (Fujifilm) for detection of feline and canine total serum BA concentration. Results were compared with a 5th-generation assay as reference method and a 3rd-generation assay, both run on a bench-top analyzer. Analytical performance was assessed at 3 different concentration ranges, and with interferences. For method comparison, samples of 60 healthy and diseased cats and 64 dogs were included. Linearity was demonstrated for a BA concentration up to 130 µmol/L in cats (r = 0.99) and 110 µmol/L in dogs (r = 0.99). The analyzer showed high precision near the lower limit of quantification of 2 µmol/L reported by the manufacturer. Intra- and inter-assay coefficients of variation were < 5% for both species and all concentrations. Interferences were observed for bilirubin (800 mg/L) and lipid (4 g/L). There was excellent correlation with the reference method for feline (rs = 0.98) and canine samples (rs = 0.97), with proportional biases of 6.7% and −1.3%, respectively. However, a large bias (44.1%) was noted when the POCA was compared to the 3rd-generation assay. Total observed error was less than total allowable error at the 3 concentrations. The POCA reliably detected feline and canine BA in clinically relevant concentrations.

Feline comorbidities: What do we really know about feline triaditis?

Feline triaditis describes concurrent pancreatitis, cholangitis and inflammatory bowel disease (IBD). The reported prevalence is 17-39% in ill referral patients. While the aetiology is poorly understood, it is known to include infectious, autoimmune and physical components. What is not known is whether different organs are affected by different diseases, or the same process; indeed, triaditis may be part of a multiorgan inflammatory disease. Feline gastrointestinal tract anatomy plays its role too. Specifically, the short small intestine, high bacterial load and anatomic feature whereby the pancreatic duct joins the common bile duct before entering the duodenal papilla all increase the risk of bacterial reflux and parenchymal inflammation. Inflammation may also be a sequela of bowel bacterial translocation and systemic bacteraemia. Cholangitis, pancreatitis and IBD manifest with overlapping, vague and non-specific clinical signs. Cholangitis may be accompanied by increased serum liver enzymes, total bilirubin and bile acid concentrations, and variable ultrasonographic changes. A presumptive diagnosis of pancreatitis is based on increased serum pancreatic lipase immunoreactivity or feline pancreas-specific lipase, and/or abnormal pancreatic changes on ultrasonography, though these tests have low sensitivity. Diagnosis of IBD is challenging without histopathology; ultrasound findings vary from normal to mucosal thickening or loss of layering. Triaditis may cause decreased serum folate or cobalamin (B12) concentrations due to intestinal disease and/or pancreatitis. Triaditis can only be confirmed with histopathology; hence, it remains a presumptive diagnosis in most cases. The literature on feline triaditis, pancreatitis, cholangitis and IBD is reviewed, focusing on histopathology, clinical significance and diagnostic challenges. Current management recommendations are provided. Further studies are needed to understand the complex pathophysiology, and in turn improve diagnosis and treatment.