Ursodeoxycholic acid therapy in hepatobiliary disease

Cardioprotective Effects of Ursodeoxycholic Acid in Isoprenaline-Induced Myocardial Injury in Rats

Patients suffering from cholelithiasis have an increased risk of developing cardiovascular complications, particularly ischemic myocardial disease. Ursodeoxycholic acid (UDCA), already used in clinical practice for the treatment of cholelithiasis and related conditions, has proven antioxidative, anti-inflammatory, and cytoprotective effects. Therefore, the aim of this study was to investigate the cardioprotective effect of UDCA pre-treatment on isoprenaline-induced myocardial injury in rats. Male Wistar albino rats were randomized into four groups. Animals were pre-treated for 10 days with propylene glycol + saline on days 9 and 10 (control), 10 days with propylene glycol + isoprenaline on days 9 and 10 (I group), 10 days with UDCA + saline on days 9 and 10 (UDCA group), and 10 days with UDCA + isoprenaline on days 9 and 10 (UDCA + I group). UDCA pre-treatment significantly reduced values of high-sensitivity troponin I (hsTnI) and aspartate aminotransferase (AST) cardiac markers (p < 0.001 and p < 0.01, respectively). The value of thiobarbituric acid reactive substances (TBARS) was also decreased in the UDCA + I group compared to the I group (p < 0.001). UDCA also significantly increased glutathione (GSH) levels, while showing a tendency to increase levels of superoxide dismutase (SOD) and catalase (CAT). The level of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) expression, a key regulatory gene of inflammation, was diminished when UDCA was administered. A reduction of cardiac damage was also observed in the UDCA pre-treated group. In conclusion, UDCA pre-treatment showed a cardioprotective effect on isoprenaline-induced myocardial injury in rats, primarily by reducing oxidative stress and inflammation.

Ursodeoxycholic Acid Modulates the Interaction of miR-21 and Farnesoid X Receptor and NF-κB Signaling

(1) Background: This study investigates the effects of Ursodeoxycholic acid (UDCA) on NF-κB signaling, farnesoid X receptor (FXR) singling, and microRNA-21 in HepG2 cells. (2) Methods: HepG2 cells were treated with lipopolysaccharide (LPS) to simulate hepatic inflammation. The investigation focused on the expression of NF-κB activation, which was analyzed using Western blot, confocal microscopy, and Electrophoretic Mobility-shift Assays (EMSA). Additionally, NF-κB and farnesoid X receptor (FXR) singling expressions of micro-RNA-21, COX-2, TNF-α, IL-6, cyp7A1, and shp were assessed by RT-PCR. (3) Results: UDCA effectively downregulated LPS-induced expressions of NF-κB/65, p65 phosphorylation, and also downregulated FXR activity by Western blot. Confocal microscopy and EMSA results confirmed UDCA's role in modulating NF-κB signaling. UDCA reduced the expressions of LPS-induced COX-2, TNF-α, and IL-6, which were related to NF-κB signaling. UDCA downregulated LPS-induced cyp7A1 gene expression and upregulated shp gene expression, demonstrating selective gene regulation via FXR. UDCA also significantly decreased micro-RNA 21 levels. (4) Conclusions: This study demonstrates UDCA's potent anti-inflammatory effects on NF-κB and FXR signaling pathways, and thus its potential to modulate hepatic inflammation and carcinogenesis through interactions with NF-κB and FXR. The decrease in micro-RNA 21 expression further underscores its therapeutic potential.

Potentials and limitations of pharmaceutical and pharmacological applications of bile acids in hearing loss treatment

Hearing loss is a worldwide epidemic, with approximately 1.5 billion people currently struggling with hearing-related conditions. Currently, the most wildly used and effective treatments for hearing loss are primarily focus on the use of hearing aids and cochlear implants. However, these have many limitations, highlighting the importance of developing a pharmacological solution that may be used to overcome barriers associated with such devices. Due to the challenges of delivering therapeutic agents to the inner ear, bile acids are being explored as potential drug excipients and permeation enhancers. This review, therefore, aims to explore the pathophysiology of hearing loss, the challenges in treatment and the manners in which bile acids could potentially aid in overcoming these challenges.

Biliary Strictures: Etiologies and Medical Management

Biliary strictures have several etiologies that can broadly be classified into benign and malignant causes. The clinical presentation is variable with strictures identified incidentally on imaging or during the evaluation of routine laboratory abnormalities. Symptoms and cholangitis lead to imaging that can diagnose biliary strictures. The diagnosis and medical management of biliary strictures will be discussed in this article.

Impact of Pharmaceutical Prophylaxis on Radiation-Induced Liver Disease Following Radioembolization

Simple Summary

Radioembolization has failed to prove survival benefit in randomized trials, and, depending on various factors including tumor biology, response rates may vary considerably. Studies showed positive correlations between survival and absorbed tumor dose. Therefore, increasing currently prescribed tumor doses may be favorable for improving patient outcomes. The dominant limiting factor for increasing RE dose prescriptions is the relatively low tolerance of liver parenchyma to radiation with the possible consequence of a radiation-induced liver disease. Advances in RILD prevention may help increasing tolerable radiation doses to improve patient outcomes. Our study aimed to evaluate the impact of post-therapeutic RILD-prophylaxis in a cohort of intensely pretreated liver metastatic breast cancer patients. The results of this study as well as pathophysiological considerations warrant further investigations of RILD prophylaxis to increase dose prescriptions in radioembolization.

Abstract

Background: Radioembolization (RE) with yttrium-90 (⁹⁰Y) resin microspheres yields heterogeneous response rates in with primary or secondary liver cancer. Radiation-induced liver disease (RILD) is a potentially life-threatening complication with higher prevalence in cirrhotics or patients exposed to previous chemotherapies. Advances in RILD prevention may help increasing tolerable radiation doses to improve patient outcomes. This study aimed to evaluate the impact of post-therapeutic RILD-prophylaxis in a cohort of intensely pretreated liver metastatic breast cancer patients; Methods: Ninety-three patients with liver metastases of breast cancer received RE between 2007 and 2016. All Patients received RILD prophylaxis for 8 weeks post-RE. From January 2014, RILD prophylaxis was changed from ursodeoxycholic acid (UDCA) and prednisolone (standard prophylaxis [SP]; n = 59) to pentoxifylline (PTX), UDCA and low-dose low molecular weight heparin (LMWH) (modified prophylaxis (MP); n = 34). The primary endpoint was toxicity including symptoms of RILD; Results: Dose exposure of normal liver parenchyma was higher in the modified vs. standard prophylaxis group (47.2 Gy (17.8–86.8) vs. 40.2 Gy (12.5–83.5), p = 0.017). All grade RILD events (mild: bilirubin ≥ 21 µmol/L (but <30 μmol/L); severe: (bilirubin ≥ 30 µmol/L and ascites)) were observed more frequently in the SP group than in the MP group, albeit without significance (7/59 vs. 1/34; p = 0.140). Severe RILD occurred in the SP group only (n = 2; p > 0.1). ALBI grade increased in 16.7% patients in the MP and in 27.1% patients in the SP group, respectively (group difference not significant); Conclusions: At established dose levels, mild or severe RILD events proved rare in our cohort. RILD prophylaxis with PTX, UDCA and LMWH appears to have an independent positive impact on OS in patients with metastatic breast cancer and may reduce the frequency and severity of RILD. Results of this study as well as pathophysiological considerations warrant further investigations of RILD prophylaxis presumably targeting combinations of anticoagulation (MP) and antiinflammation (SP) to increase dose prescriptions in radioembolization.

[Biliary sludge: pathogenesis, etiology and drug therapy]

AIM

To evaluate the effectiveness of the use of ursodeoxycholic acid (UDCA) for the treatment of biliary sludge (BS) and to compare the therapeutic effectiveness of the German substance UDCA and generic drugs from other manufacturers.

MATERIALS AND METHODS

The study involved 65 patients diagnosed with BS (K80.8). To assess the severity of BS, ultrasound of the gallbladder was performed before treatment, after 1, 3, 6 months during therapy, as well as an assessment of its contractility. All patients were randomized into 2 groups. Patients of the main group received UDCA Ursofalk (Germany) at a dose of 10 mg/kg for at least 6 months. Patients in the comparison group received UDCA (another manufacturer) at a dose of 10 mg/kg for at least 6 months.

RESULTS

After 3 months of follow-up, the number of patients with dissolved sludge in the main group was 87.1%, while in the comparison group 50%. In 71% of patients, the normalization of the lean volume of the gallbladder was noted, and in the comparison group only in 47.1%. After 6 months of follow-up, complete resolution of BS in the main group was observed in 93.5% of cases, and in the comparison group in 73.6% of cases.

CONCLUSION

As a result of the study, the high effectiveness of Ursofalk during oral litolysis in patients with stage I GI (BS) in the first 3 months of therapy, as well as the normalization of the contractile function of the gallbladder, were noted.

Prolonged ursodeoxycholic acid administration reduces acute ischaemia-induced arrhythmias in adult rat hearts

Acute myocardial ischaemia and reperfusion (I-R) are major causes of ventricular arrhythmias in patients with a history of coronary artery disease. Ursodeoxycholic acid (UDCA) has previously been shown to be antiarrhythmic in fetal hearts. This study was performed to investigate if UDCA protects against ischaemia-induced and reperfusion-induced arrhythmias in the adult myocardium, and compares the effect of acute (perfusion only) versus prolonged (2 weeks pre-treatment plus perfusion) UDCA administration. Langendorff-perfused adult Sprague-Dawley rat hearts were subjected to acute regional ischaemia by ligation of the left anterior descending artery (10 min), followed by reperfusion (2 min), and arrhythmia incidence quantified. Prolonged UDCA administration reduced the incidence of acute ischaemia-induced arrhythmias (p = 0.028), with a reduction in number of ventricular ectopic beats during the ischaemic phase compared with acute treatment (10 ± 3 vs 58 ± 15, p = 0.036). No antiarrhythmic effect was observed in the acute UDCA administration group. Neither acute nor prolonged UDCA treatment altered the incidence of reperfusion arrhythmias. The antiarrhythmic effect of UDCA may be partially mediated by an increase in cardiac wavelength, due to the attenuation of conduction velocity slowing (p = 0.03), and the preservation of Connexin43 phosphorylation during acute ischaemia (p = 0.0027). The potential antiarrhythmic effects of prolonged UDCA administration merit further investigation.

Single Procedure Saline Lavage for Treatment of Inspissated Bile

Inspissated bile syndrome is a rare cause of cholestatic jaundice in infancy, occurring due to obstruction of the biliary ducts and gallbladder by biliary sludge. Traditional methods of treatment include surgical drainage or cholecystostomy drain placement. Both can be associated with complications and prolonged admission. We present 2 cases treated with a single percutaneous needle puncture of the gallbladder followed by saline lavage. Two neonates presented with cholestatic jaundice and sonographic evidence of biliary sludge and dilation of the common bile duct. Single sonographic-guided needle puncture of the gallbladder was followed by irrigation with saline. Clearing of the biliary sludge was confirmed by sonography and cholecystocholangiography. There was resolution of the cholestatic jaundice, with no complications or repeat procedures.

Opposing effects of bile acids deoxycholic acid and ursodeoxycholic acid on signal transduction pathways in oesophageal cancer cells

Ursodeoxycholic acid (UDCA) was reported to reduce bile acid toxicity, but the mechanisms underlying its cytoprotective effects are not fully understood. The aim of the present study was to examine the effects of UDCA on the modulation of deoxycholic acid (DCA)-induced signal transduction in oesophageal cancer cells. Nuclear factor-κB (NF-κB) and activator protein-1 (AP-1) activity was assessed using a gel shift assay. NF-κB activation and translocation was performed using an ELISA-based assay and immunofluorescence analysis. COX-2 expression was analysed by western blotting and COX-2 promoter activity was assessed by luciferase assay. DCA induced NF-κB and AP-1 DNA-binding activities in SKGT-4 and OE33 cells. UDCA pretreatment inhibited DCA-induced NF-κB and AP-1 activation and NF-κB translocation. This inhibitory effect was coupled with a blockade of IκB-α degradation and inhibition of phosphorylation of IKK-α/β and ERK1/2. Moreover, UDCA pretreatment inhibited COX-2 upregulation. Using transient transfection of the COX-2 promoter, UDCA pretreatment abrogated DCA-induced COX-2 promoter activation. In addition, UDCA protected oesophageal cells from the apoptotic effects of deoxycholate. Our findings indicate that UDCA inhibits DCA-induced signalling pathways in oesophageal cancer cells. These data indicate a possible mechanistic role for the chemopreventive actions of UDCA in oesophageal carcinogenesis.

Neonatal Cholestasis

Neonatal jaundice is common and usually not concerning when it is secondary to unconjugated hyperbilirubinemia, below the neurotoxic level, and resolves early. Primary care providers should be vigilant, however, about evaluating infants in whom jaundice presents early, is prolonged beyond 2 weeks of life, or presents at high levels. Even in well-appearing infants, fractionated (direct and indirect) bilirubin levels should be obtained in these clinical scenarios to evaluate for potential cholestasis. This review presents an approach to the evaluation of a jaundiced infant and discusses diagnosis and management of several causes of neonatal cholestasis.

Liraglutide-related cholelithiasis

Liraglutide is a glucagon-like peptide-1 analog and recently started to be using as an incretin-based treatment for diabetes mellitus. Liraglutide causes some adverse affects including nausea, vomiting, acute nasopharyngitis and acute pancreatitis. However, development of liraglutide-dependent cholelithiasis has not been reported in the literature. A 75-year-old female patient had been diagnosed with type 2 diabetes mellitus for 10 years and she has been treated by liraglutide for 6 months. The patient was admitted to the emergency service due to sudden onset of abdominal pain. After laboratory and imaging studies, she was diagnosed with acute cholecystitis and cholelithiasis. And then patient's oral intake was stopped, intravenous fluid and ceftriaxone 2 g/day were started. Furthermore, liraglutide treatment discontinued and ursodeoxycholic acid (UDCA) was started to treat cholelithiasis. During follow-up, abdominal pain completely relieved. Hepatobiliary ultrasonography in sixth month follow-up showed entirely regression of cholelithiasis. Any liraglutide-related cholelithiasis case has not been reported in the literature previously. Therefore, our case is the first case. Especially, elderly diabetic patients who are started to liraglutide treatment should be monitored closely for the formation of cholelithiasis. UDCA treatment would be an alternative prior to surgical treatment for liraglutide-related cholelithiasis.

Prophylaxis and treatment recommendations for sinusoidal obstruction syndrome in adult and pediatric patients undergoing hematopoietic stem cell transplant: a review of the literature

Sinusoidal obstruction syndrome, a complication occurring early after hematopoietic stem cell transplantation, is a concern for clinicians. There are no guidelines to direct clinicians on the optimal way to prevent and treat this disease. Newer data show that defibrotide is a promising drug both for prevention and treatment, although it is not yet FDA approved.

Prospective randomized trial of enoxaparin, pentoxifylline and ursodeoxycholic acid for prevention of radiation-induced liver toxicity

BACKGROUND/AIM

Targeted radiotherapy of liver malignancies has found to be effective in selected patients. A key limiting factor of these therapies is the relatively low tolerance of the liver parenchyma to radiation. We sought to assess the preventive effects of a combined regimen of pentoxifylline (PTX), ursodeoxycholic acid (UDCA) and low-dose low molecular weight heparin (LMWH) on focal radiation-induced liver injury (fRILI).

METHODS AND MATERIALS

Patients with liver metastases from colorectal carcinoma who were scheduled for local ablation by radiotherapy (image-guided high-dose-rate interstitial brachytherapy) were prospectively randomized to receive PTX, UDCA and LMWH for 8 weeks (treatment) or no medication (control). Focal RILI at follow-up was assessed using functional hepatobiliary magnetic resonance imaging (MRI). A minimal threshold dose, i.e. the dose to which the outer rim of the fRILI was formerly exposed to, was quantified by merging MRI and dosimetry data.

RESULTS

Results from an intended interim-analysis made a premature termination necessary. Twenty-two patients were included in the per-protocol analysis. Minimal mean hepatic threshold dose 6 weeks after radiotherapy (primary endpoint) was significantly higher in the study treatment-group compared with the control (19.1 Gy versus 14.6 Gy, p = 0.011). Qualitative evidence of fRILI by MRI at 6 weeks was observed in 45.5% of patients in the treatment versus 90.9% of the control group. No significant differences between the groups were observed at the 12-week follow-up.

CONCLUSIONS

The post-therapeutic application of PTX, UDCA and low-dose LMWH significantly reduced the extent and incidence fRILI at 6 weeks after radiotherapy. The development of subsequent fRILI at 12 weeks (4 weeks after cessation of PTX, UDCA and LMWH during weeks 1-8) in the treatment group was comparable to the control group thus supporting the observation that the agents mitigated fRILI.

TRIAL REGISTRATION

EU clinical trials register 2008-002985-70 ClinicalTrials.gov NCT01149304.

Metal Zn(II), Cu(II), Ni (II) complexes of ursodeoxycholic acid as putative anticancer agents

The aim of the study was to evaluate the influence of metal [Zn(II), Cu(II), Ni(II)] complexes with ursodeoxycholic acid (UDCA) on the viability and proliferation of tumour and non-tumour cells. Cell lines established from retrovirus-transformed chicken hepatoma (LSCC-SF-Mc29) and rat sarcoma (LSR-SF-SR) as well as from human cancers of the breast (MCF-7), uterine cervix (HeLa), lung (A549) and liver (HepG2) were used as model systems. Non-tumour human embryo (Lep-3) cells were also included in some of the experiments. The investigations were carried out by the thiazolyl blue tetrazolium bromide (MTT) test, neutral red uptake cytotoxicity assay, crystal violet staining, double staining with acridine orange and propidium iodide and the colony-forming method. The results obtained revealed that: (1) UDCA and its metal complexes in the tested concentrations decreased (to a varying degree) the viability and proliferation of the treated cells in a time- and concentration-dependent manner; (2) chicken hepatoma (LSCC-SF-Mc29) cells were most sensitive to the cytotoxic and antiproliferative action of the compounds tested, followed by rat sarcoma (LSR-SF-SR) cells; (3) Cu‒UDCA and Ni‒UDCA were more effective against animal LSCC-SF-Mc29 and LSR-SF-SR cells, while Zn‒UDCA significantly decreased the viability and proliferation of human tumour cell lines; (4) applied independently, UDCA expressed lower cytotoxic/cytostatic activity as compared to metal complexes; and (5) the sensitivity of the non-tumour embryonic Lep-3 cells to the effects of UDCA and its metal complexes was comparable or even higher than those of the human tumour cells.

In Barrett's esophagus patients and Barrett's cell lines, ursodeoxycholic acid increases antioxidant expression and prevents DNA damage by bile acids

Hydrophobic bile acids like deoxycholic acid (DCA), which cause oxidative DNA damage and activate NF-κB in Barrett's metaplasia, might contribute to carcinogenesis in Barrett's esophagus. We have explored mechanisms whereby ursodeoxycholic acid (UDCA, a hydrophilic bile acid) protects against DCA-induced injury in vivo in patients and in vitro using nonneoplastic, telomerase-immortalized Barrett's cell lines. We took biopsies of Barrett's esophagus from 21 patients before and after esophageal perfusion with DCA (250 μM) at baseline and after 8 wk of oral UDCA treatment. DNA damage was assessed by phospho-H2AX expression, neutral CometAssay, and phospho-H2AX nuclear foci formation. Quantitative PCR was performed for antioxidants including catalase and GPX1. Nrf2, catalase, and GPX1 were knocked down with siRNAs. Reporter assays were performed using a plasmid construct containing antioxidant responsive element. In patients, baseline esophageal perfusion with DCA significantly increased phospho-H2AX and phospho-p65 in Barrett's metaplasia. Oral UDCA increased GPX1 and catalase levels in Barrett's metaplasia and prevented DCA perfusion from inducing DNA damage and NF-κB activation. In cells, DCA-induced DNA damage and NF-κB activation was prevented by 24-h pretreatment with UDCA, but not by mixing UDCA with DCA. UDCA activated Nrf2 signaling to increase GPX1 and catalase expression, and protective effects of UDCA pretreatment were blocked by siRNA knockdown of these antioxidants. UDCA increases expression of antioxidants that prevent toxic bile acids from causing DNA damage and NF-κB activation in Barrett's metaplasia. Elucidation of this molecular pathway for UDCA protection provides rationale for clinical trials on UDCA for chemoprevention in Barrett's esophagus.

Biliary cast syndrome in an opium inhaler

Biliary cast syndrome (BCS) is an uncommon complication which is mostly described in orthotopic liver transplantation. However, BCS has also been reported rarely in non-liver transplant patients. We describe a male long-term opium inhaler with BCS who underwent successful endoscopic cast removal by balloon enteroscopy-guided endoscopic retrograde cholangiopancreatography. A 52-year-old man, who was a known case of opium addiction, presented with the chief complaint of epigastric pain for 1 week prior to admission. Routine laboratory evaluation revealed cholestatic liver enzyme elevation. A cholestatic pattern was seen in radiographic modalities. Endoscopic retrograde cholangiopancreatography showed a linear filling defect in the intra- and extrahepatic duct. A long biliary cast was successfully removed using an extractor balloon. After removal of the biliary cast the patient is receiving ursodeoxycholic acid and does not report any problem 4 months after treatment. It seems that biliary dyskinesia due to long-term opium use can be a predisposing factor for biliary cast formation.

Improved survival with ursodeoxycholic acid prophylaxis in allogeneic stem cell transplantation: long-term follow-up of a randomized study

We report the long-term results of a prospective randomized study on the use of ursodeoxycholic acid (UDCA) for prevention of hepatic complications after allogeneic stem cell transplantation. Two hundred forty-two patients, 232 with malignant disease, were randomized to receive (n = 123) or not to receive (n = 119) UDCA from the beginning of the conditioning until 90 days post-transplantation. The results were reported after 1-year follow-up. UDCA administration reduced significantly the proportion of patients developing high serum bilirubin levels as well as the incidence of severe acute graft-versus-host disease (GVHD), liver GVHD, and intestinal GVHD. In the UDCA prophylaxis group, nonrelapse mortality (NRM) was lower and overall survival better than in the control group. After a 10-year follow-up, the difference in the survival and NRM in favor of the UDCA-treated group, seen at 1 year, was maintained (survival 48% versus 38%, P = .037; NRM 28% versus 41%, P = .01). A landmark analysis in patients surviving at 1 year post-transplantation showed no significant differences between the study groups in the long-term follow-up in chronic GVHD, relapse rate, NRM, disease-free survival, or overall survival. These long-term results continue to support the useful role of UDCA in the prevention of transplant-related complications in allogeneic transplantation.

The effect of ursodeoxycholic acid in liver functional restoration of patients with obstructive jaundice after endoscopic treatment: a prospective, randomized, and controlled study

Background

In patients with obstructive jaundice, multi-organ dysfunction may develop.

Methods/Design

This trial is a prospective, open-label, randomized, and controlled study with the objective to evaluate the effect of ursodeoxycholic acid in liver functional restoration in patients with obstructive jaundice after endoscopic treatment. The aim of this study is to evaluate the effect of ursodeoxycholic acid in liver functional restoration of patients with obstructive jaundice after endoscopic treatment. The hypothesis of this trial is that patients with obstructive jaundice, in which will be administered UDCA, in the early phase after endoscopic intervention will have better and faster functional restoration of the liver than patients in the control group.

Patients with obstructive jaundice, randomly, will be divided into two groups: (A) test group in which will be administered ursodeoxycholic acid twenty-four hours after endoscopic procedure and will last fourteen days, and (B) control group.

Serum-testing will include determination of bilirubin, alanine transaminase, aspartate transaminase, gama-glutamil transpeptidase, alkaline phosphatase, albumin, and cholesterol levels. These parameters will be determined one day prior endoscopic procedure, and on the third, fifth, seventh, tenth, twelfth and fourteenth days after endoscopic intervention.

Discussion

This trial is a prospective, open-label, randomized, and controlled study to asses the effect of ursodeoxycholic acid in liver functional restoration of patients with obstructive jaundice in the early phase after endoscopic treatment.

Trial registration

ClinicalTrials.gov, NCT01688375

Sex differences in the hepatic cholesterol sensing mechanisms in mice

Cholesterol is linked to many multifactorial disorders, including different forms of liver disease where development and severity depend on the sex. We performed a detailed analysis of cholesterol and bile acid synthesis pathways at the level of genes and metabolites combined with the expression studies of hepatic cholesterol uptake and transport in female and male mice fed with a high-fat diet with or without cholesterol. Lack of dietary cholesterol led to a stronger response of the sterol sensing mechanism in females, resulting in higher expression of cholesterogenic genes compared to males. With cholesterol in the diet, the genes were down-regulated in both sexes; however, males maintained a more efficient hepatic metabolic flux through the pathway. Females had higher content of hepatic cholesterol but this was likely not due to diminished excretion but rather due to increased synthesis and absorption. Dietary cholesterol and sex were not important for gallbladder bile acids composition. Neither sex up-regulated Cyp7a1 upon cholesterol loading and there was no compensatory up-regulation of Abcg5 or Abcg8 transporters. On the other hand, females had higher expression of the Ldlr and Cd36 genes. These findings explain sexual dimorphism of cholesterol metabolism in response to dietary cholesterol in a high-fat diet in mice, which contributes to understanding the sex-basis of cholesterol-associated liver diseases.

Specific bile acids inhibit hepatic fatty acid uptake in mice

Bile acids are known to play important roles as detergents in the absorption of hydrophobic nutrients and as signaling molecules in the regulation of metabolism. We tested the novel hypothesis that naturally occurring bile acids interfere with protein-mediated hepatic long chain free fatty acid (LCFA) uptake. To this end, stable cell lines expressing fatty acid transporters as well as primary hepatocytes from mouse and human livers were incubated with primary and secondary bile acids to determine their effects on LCFA uptake rates. We identified ursodeoxycholic acid (UDCA) and deoxycholic acid (DCA) as the two most potent inhibitors of the liver-specific fatty acid transport protein 5 (FATP5). Both UDCA and DCA were able to inhibit LCFA uptake by primary hepatocytes in a FATP5-dependent manner. Subsequently, mice were treated with these secondary bile acids in vivo to assess their ability to inhibit diet-induced hepatic triglyceride accumulation. Administration of DCA in vivo via injection or as part of a high-fat diet significantly inhibited hepatic fatty acid uptake and reduced liver triglycerides by more than 50%.

CONCLUSION

The data demonstrate a novel role for specific bile acids, and the secondary bile acid DCA in particular, in the regulation of hepatic LCFA uptake. The results illuminate a previously unappreciated means by which specific bile acids, such as UDCA and DCA, can impact hepatic triglyceride metabolism and may lead to novel approaches to combat obesity-associated fatty liver disease.

Ursodeoxycholic acid therapy in cystic fibrosis liver disease--a retrospective long-term follow-up case-control study

BACKGROUND

The prevention and treatment of liver disease associated with cystic fibrosis remain a significant unresolved problem.

AIM

To assess the long-term effects of continuous ursodeoxycholic acid (UDCA) therapy in cystic fibrosis patients with constantly elevated serum liver enzymes.

METHODS

The primary endpoint was the incidence of overt liver disease. Between 1989 and 2005, UDCA treatment was started in 98 subjects from a cohort of 382 cystic fibrosis patients. These subjects were compared with a historic control group of 352 subjects who attended our centre between 1975 and 1989 before UDCA became standard treatment. For the long-term comparison of liver function and lung function tests, a group of 98 matched contemporary cystic fibrosis patients were compared with the 98 subjects treated with UDCA.

RESULTS

Overt liver disease developed in only one of the 382 patients who was treated with UDCA for increased serum liver enzymes compared with nine patients in the historic control group (P < 0.05). Serum liver enzyme levels declined in most patients receiving UDCA treatment during the 17-year follow-up (87/98, P < 0.05). No difference was seen in lung function between subjects with cystic fibrosis-related liver disease and the matched controls.

CONCLUSIONS

Regular and systematic screening for liver involvement enables early introduction of UDCA therapy in affected cystic fibrosis patients, reduces the development of severe liver disease and leads to a significant and persistent improvement in serum liver tests, without impairing long-term pulmonary outcome.

A controlled trial of erythromycin and UDCA in premature infants during parenteral nutrition in minimizing feeding intolerance and liver function abnormalities

OBJECTIVE

To compare the effectiveness of oral erythromycin versus ursodeoxycholic acid (UDCA) treatment in preventing feeding intolerance and liver function abnormalities.

STUDY DESIGN

A prospective, double blind, randomized, controlled trial in which three groups of preterm infants (birth weight <1500 g) were randomized to erythromycin (12.5 mg kg(-1) per day), UDCA (5 mg kg(-1) every 6 h) or placebo treatment. During the period 352 infants were admitted to our unit of which 75 infants whose parents accepted participation were enrolled in the study. Full enteral feeding or intestinal failure-associated liver disease was considered as the primary outcome measures.

RESULTS

Time to achieve full feeding after beginning the treatment was significantly shorter in the erythromycin group (P=0.014). γ-Glutamyl transpeptidase levels in the placebo group were significantly higher than in the intervention groups (P=0.001). GTT level was slightly lower in UDCA groups than erythromycin.

CONCLUSION

Oral erythromycin was most effective in facilitating enteral feeding and UDCA was most effective in preventing cholestasis in very low birth weight infants. Prophylactic usage of UDCA could be considered in infants with prolonged parenteral nutrition.

Deoxycholic acid causes DNA damage while inducing apoptotic resistance through NF-κB activation in benign Barrett's epithelial cells

Gastroesophageal reflux is associated with adenocarcinoma in Barrett's esophagus, but the incidence of this tumor is rising, despite widespread use of acid-suppressing medications. This suggests that refluxed material other than acid might contribute to carcinogenesis. We looked for potentially carcinogenetic effects of two bile acids, deoxycholic acid (DCA) and ursodeoxycholic acid (UDCA), on Barrett's epithelial cells in vitro and in vivo. We exposed Barrett's (BAR-T) cells to DCA or UDCA and studied the generation of reactive oxygen/nitrogen species (ROS/RNS); expression of phosphorylated H2AX (a marker of DNA damage), phosphorylated IkBα, and phosphorylated p65 (activated NF-κB pathway proteins); and apoptosis. During endoscopy in patients, we took biopsy specimens of Barrett's mucosa before and after esophageal perfusion with DCA or UDCA and assessed DNA damage and NF-κB activation. Exposure to DCA, but not UDCA, resulted in ROS/RNS production, DNA damage, and NF-κB activation but did not increase the rate of apoptosis in BAR-T cells. Pretreatment with N-acetyl-l-cysteine (a ROS scavenger) prevented DNA damage after DCA exposure, and DCA did induce apoptosis in cells treated with NF-κB inhibitors (BAY 11-7085 or AdIκB superrepressor). DNA damage and NF-κB activation were detected in biopsy specimens of Barrett's mucosa taken after esophageal perfusion with DCA, but not UDCA. These data show that, in Barrett's epithelial cells, DCA induces ROS/RNS production, which causes genotoxic injury, and simultaneously induces activation of the NF-κB pathway, which enables cells with DNA damage to resist apoptosis. We have demonstrated molecular mechanisms whereby bile reflux might contribute to carcinogenesis in Barrett's esophagus.

Medical management of motility disorders in patients with intestinal failure: a focus on necrotizing enterocolitis, gastroschisis, and intestinal atresia

BACKGROUND

Intestinal failure (IF) is the dependence upon parenteral nutrition to maintain minimal energy requirements for growth and development. It may occur secondary to a loss of bowel length, disorders of motility, or both. Short bowel syndrome (SBS) is a malabsorptive state resulting from surgical resection, congenital defect, or diseases associated with loss of absorptive surface area. A particularly vexing problem is associated with whole bowel and/or segmental intestinal dysmotility. Motility disorders within the context of SBS and IF may relate to rapid intestinal transit secondary to loss of intestinal length, dysmotility associated with loss or poor antegrade peristalsis, or gastroparesis. Therapy may be classified into medical (prokinetic and antidiarrheal agents) and surgical to deal with the overdistended poorly motile bowel.

METHODS

We performed a systematic review of the literature pertaining to IF, SBS, and dysmotility in the pediatric population with gastroschisis, necrotizing enterocolitis, and intestinal atresia. In addition to the available treatment options, we have provided a review of the literature and a summary of the available evidence.

CONCLUSION

Despite relatively poor level of evidence regarding the application of promotility and antidiarrheal medications in patients with SBS and IF, these agents continue to be used. Herein, we provide a review of the physiology and pathophysiology of intestinal motility/dysmotility and available strategies for the use of promotility and antidiarrheal agents in patients with IF/SBS.

Late diagnosed Wilson disease with hepatic and neurological manifestations

A 50-year-old woman was referred to our hospital due to liver dysfunction and progressive neurological symptoms. She had previously been diagnosed with nonalcoholic steatohepatitis (NASH). Ursodeoxycholic acid (UDCA) had effectively normalized her serum aminotransferase levels, however, she presented with loss of balance, dysarthria and difficulty in handwriting. Autoantibodies and hepatitis virus markers were negative. Serum ceruloplasmin and copper levels were noted to be 9 mg/dL and 32 µg/dL, respectively. The 24-h urinary copper excretion was 331.8 µg/day. Kayser-Fleischer ring was demonstrated. Histological examination of the liver revealed inflammatory infiltrate and fibrosis, and the hepatic copper concentration was 444.4 µg/g dry weight. We diagnosed her as having Wilson disease and started treatment with trientine. Immuohistochemistry for keratin 8 and p62 demonstrated Mallory-Denk bodies. Many of the p62-expressing cells were positive for 4-Hydroxy-2-nonenal (HNE). Few Ki-67-positive hepatocytes were present in the liver. Wilson disease is one of the causes of NASH and UDCA may be a supportive therapeutic agent for Wilson disease. Cell proliferation is suppressed under copper-loaded conditions and this phenomenon may be associated with the clinical course of Wilson disease.

Combined endoscopic and ursodeoxycholic acid treatment of biliary cast syndrome in a non-transplant patient

A 76-year-old diabetic man underwent cholecystectomy for gangrenous calculous cholecystitis. His postoperative course was complicated by the development of Candida albicans esophagitis necessitating antifungal therapy, and total parenteral nutrition (TPN) for 15 d. Seven weeks after cholecystectomy, he presented with cholangitis. Endoscopic retrograde cholangiopancreatography (ERCP) demonstrated extrahepatic filling defects. Despite endoscopic extraction of a biliary cast, cholestasis remained unchanged. Oral administration of ursodeoxycholic acid (UDCA), 750 mg/d, resulted in normalization of liver function tests. We, therefore, propose for the first time, combined endoscopic plus UDCA treatment for the management of biliary cast syndrome.

Progress in diagnosis and treatment of cholestasis

Cholestasis can be considered a clinically frequent syndrome caused by complicated factors. Although investigation of cholestasis has been carried out at molecular biology level its pathogenesis can be more clearly recognized. However, the diagnosis and management of intrahepatic cholestasis has not improved. How to identify the pathophysiological and pharmacological targets of cholestatic liver disease is a challenging issue facing clinicians, pathophysiologists and pharmacologists.

Effects of long term hydrophilic bile acid therapy on in vitro contraction of gallbladder muscle strips in patients with cholesterol gallstones

AIM: To evaluate ursodeoxycholic acid (UDCA) therapy on the in vitro contraction of gallbladder smooth muscle strips from cholesterol gallstone patients.

METHODS: The contraction forces of gallbladder smooth muscle strips from 28 patients with cholesterol gallstones treated with UDCA were compared with contraction forces from 14 untreated patients. The strips were stimulated with increasing concentrations of cholecystokinin-8 (CCK-8).

RESULTS: Although the contraction forces that developed in response to CCK-8 were higher in strips from specimens of UDCA treated patients compared to untreated patients, longer treatment periods (6-wk) caused more contraction responses than the short treatment period of 3-wk (F = 19.297, 1.85 ± 0.22 g vs 1.70 ± 0.10 g, P < 0.01). Contraction forces developed with maximal stimulation with KCl in the 6-wk treatment group were also higher than contraction forces in the untreated group (F = 4.274, 3.77 ± 0.45 g vs 3.30 ± 0.30 g, P < 0.05).

CONCLUSION: Six-week UDCA treatment caused an increase in contractions of muscle strips from patients with cholesterol gallstones when compared to shorter treatment administration or controls. We suggest that extending UDCA treatment periods may cause more effective contractions in the gallbladder, and thereby increase the rate of response to treatment.

Systematic review of controlled clinical trials on the use of ursodeoxycholic acid for the prevention of hepatic veno-occlusive disease in hematopoietic stem cell transplantation

Hepatic veno-occlusive disease (HVOD) is a serious life-threatening complication of hematopoietic stem cell transplantation (HSCT). Currently, there is no optimal therapeutic strategy and preventive measures are ill-defined. Ursodeoxycholic acid (UA) is well-tolerated oral medication that has been associated with possible benefit as a prophylactic agent. We sought to summarize and quantify the clinical effects of prophylactic UA in the context of HSCT. We undertook a systematic review of studies addressing the use of UA as monotherapy or in combination with other agents in patients undergoing HSCT. The Search Strategy included MEDLINE (1966 to fourth week of March 2006), EMBASE (1980 to fourth week of March 2006), all EBM Reviews (fourth quarter of 2005), Ovid Healthstar (1966 to fourth week of March 2006), and Google Scholar on March 20, 2006. Six studies, 4 randomized clinical trials and 2 historically controlled studies, representing 824 patients were included in the review. Three randomized clinical trials comparing prophylactic UA with no treatment demonstrated reduced proportion of HVOD (relative risk [RR], 0.34; 95% confidence interval [CI], 0.17-0.66). When the analysis was limited to higher-quality studies, the beneficial effect of UA remained significant (RR, 0.36; 95% CI, 0.15-0.90). Transplant-related mortality was also reduced with the prophylactic use of UA (RR, 0.58; 95% CI, 0.35-0.95). UA did not significantly attenuate the outcomes of acute graft-versus-host disease (RR, 0.76; 95% CI, 0.53-1.09), relapse (RR, 0.77; 95% CI, 0.46-1.31), or overall survival (RR, 1.22; 95 % CI, 0.96-1.54). UA appears effective for HVOD prophylaxis in patients undergoing HSCT and should be considered as a prevention strategy by HSCT centers to reduce HVOD.

Pharmacology of bile acids and their derivatives: Absorption promoters and therapeutic agents

The role of bile acids in pharmacotherapy is reviewed in this article. The therapeutic use of bile has been recognized since ancient times. Previously bile acids were the standard treatment for gallstones where chenodeoxycholic acid and ursodeoxycholic acid were effective in promoting the dissolution of cholesterol gallstones. Today their therapeutic role looks set to expand enormously. Bile acids as absorption promoters have the potential to aid intestinal, buccal, transdermal, ocular, nasal, rectal and pulmonary absorption of various drugs at concentrations that are non-toxic. Keto derivatives of cholic acid, such as 3a,7a,dihydroxy-12-keto-5alpha-cholic acid (sodium salt and methyl ester) are potential modifiers of blood-brain barrier transport and have been shown to promote quinine uptake, enhance the analgesic effect of morphine and prolong the sleeping time induced by pentobarbital. They have also been shown to be hypoglycaemic. Bile acids as therapeutic agents have the potential to produce beneficial effects in sexually transmitted diseases, primary biliary cirrhosis, primary sclerosing cholangitis, gallstones, digestive tract diseases, cystic fibrosis, cancer and diabetes.

A case of impetigo herpetiformis associated with intrahepatic cholestasis of pregnancy

We herein reported a 26-year-old primigravida with impetigo herpetiformis and intrahepatic cholestasis of gestation. She was in gestation for 34 weeks. She had a 5-month history of pustules on the trunk and limbs that had exacerbated from 1 month before. The jaundice had also emerged lately with increased levels of serous transaminase, bilirubin and bile acid. The histopathology of the lesion confirmed the diagnosis of impetigo herpetiformis. After cesarean section and administration of glucocorticoid, the patient totally recovered.

Treatment options for chronic cholestasis in infancy and childhood

Altered bile flow physiology leads to many complications commonly seen in patients with cholestatic liver disease, regardless of the etiology. For each individual patient, a coordinated and effective treatment strategy must address the presence and the severity spectrum of malabsorption, malnutrition, vitamin and micronutrient deficiencies, pruritus, xanthomata, ascites, and liver failure, which are attributed directly or indirectly to diminished bile flow. An aggressive approach to maximizing the nutritional status of the child is vital to ensure optimal growth and development. Protein-calorie and/or fat supplementation is best discussed early. Decreasing the percentage of dietary long-chain triglycerides, providing medium-chain triglycerides, and ensuring adequate essential fatty acid and adequate protein intake may be helpful. Fat-soluble vitamin (A, D, E, and K) levels and micronutrient levels must be carefully and serially monitored and supplemented as necessary. Because the mechanisms that mediate pruritus of cholestasis remain to be determined, the use of empirical therapies continues to be standard practice. Ursodeoxycholic acid may ameliorate pruritus. Antihistamines and rifampicin may also provide temporary relief for some children. Based on the evidence that increased central opioidergic tone is present in chronic cholestasis, the use of opiate antagonists is promising but has not been evaluated in children. Selected patients with refractory pruritus that have failed maximal medical therapy have benefited from partial external biliary diversion. Ongoing dialogue with the family regarding the indications for liver transplantation is reasonable. Optimization and adherence with the pretransplant medical management enhance the chances for a successful outcome from liver transplantation. Specific to the pediatric patient, optimizing growth, development and nutrition, minimizing discomfort and disability, and aiding the child and family in coping with the stress, social, and emotional effects of chronic liver disease remain paramount.

Ursodeoxycholic acid treatment in isolated chronic graft-vs.-host disease of the liver

OBJECTIVES

Data regarding the long-term treatment of ursodeoxycholic acid (UDCA) in individuals of chronic graft-vs.-host disease (cGVHD) of the liver are limited. The aims of this prospective study were to determine whether, (i) UDCA treatment is useful as a long-term treatment for individuals with limited cGVHD of the liver following allogeneic hematopoietic cell transplantation, and (ii) the tolerability of UDCA treatment in such individuals.

METHODS

Fifteen consecutive patients with de novo isolated cGVHD of the liver were included. All individuals were treated with UDCA at a dose of 13 mg/kg/d for 1 yr. Clinical evaluation and laboratory testing were assessed at 30-d intervals during UDCA therapy and every 30 d after discontinuation of UDCA for a total of 3 months.

RESULTS

At the end of the treatment, 60% of patients with cGVHD of the liver had normal liver tests, the remaining 40% of patients demonstrated improvement in their abnormal liver tests (partial responders), whereas none of the patients had worsening of the liver tests. When compared with baseline, there was a significant decrease in the serum aminotransferases, alkaline phosphatase and gamma-glutamyl transpeptidase levels after completion of the UDCA treatment at 12 months (p < 0.01). No significant increase in serum liver enzyme tests was observed at the third month after the completion of therapy. Pruritus in seven of nine patients resolved after UDCA treatment. All patients completed their assigned treatment with no major adverse event.

CONCLUSION

Long-term UDCA therapy appears to be effective, safe and tolerable in individuals with cGVHD presenting with isolated liver involvement.

A multiagent strategy to decrease regimen-related toxicity in children undergoing allogeneic hematopoietic stem cell transplantation

Regimen-related toxicity (RRT) is a frequent cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). In this pilot study, we examined the feasibility and potential efficacy of administering a fixed combination of agents as a novel approach to reducing RRT in children undergoing HSCT. Thirty-seven patients were treated with ursodeoxycholic acid, folinic acid, vitamin E, and parenteral nutrition titrated to measured energy expenditure in the peritransplantation period. Outcomes were compared with those in historical controls (n = 131). Compliance with oral ursodeoxycholic acid and vitamin E of at least 90% was achieved in a mean of 86% (95% confidence interval, 75%-97%) of patients. In the study group, we observed (1) reduced prevalence and severity of mucositis (P = .008 and.004, respectively); (2) less severe hepatic toxicity (P = .007); and (3) shorter time to engraftment (P = .02) compared with the control group. These benefits appeared most pronounced among high-risk patients. The administration of this regimen, including oral medications, is feasible during the peritransplantation period, and it is well tolerated. The decreased RRT observed in comparison to historical controls suggests that combination approaches deserve exploration as a means of reducing the morbidity of HSCT.

Liver disease in pregnancy

Liver dysfunction during pregnancy can be caused by conditions that are specific to pregnancy or by liver diseases that are not related to pregnancy itself. This review attempts to summarize the epidemiology, pathophysiology, and management of the different pregnancy-related liver diseases, and to review different liver diseases not related to pregnancy and how they may affect or be effected by pregnancy. Some of the liver diseases specific to pregnancy can cause significant morbidity and mortality both to the mother and to the fetus, while most of the liver diseases not specific to pregnancy do not have a deleterious effect on the pregnancy itself.

Ursodeoxycholic acid (UDCA) therapy in very-low-birth-weight infants with parenteral nutrition-associated cholestasis

OBJECTIVE

To determine the effect of ursodeoxycholic acid (UDCA) in very-low-birth-weight (VLBW) infants with parenteral nutrition-associated cholestasis (PNAC).

STUDY DESIGN

A retrospective study of all VLBW infants with PNAC who were admitted to a tertiary referral center was conducted. Patients were classified as treatment group (receiving UDCA within 14 days after onset of cholestasis) or control group (no medical treatment). Patients who received abdominal surgery were excluded.

RESULTS

A total of 30 patients were recruited, including 12 in the treatment group and 18 in the control group. The demographic data, total fasting duration, onset of cholestasis, age to tolerance of full feeds, and the duration of parenteral nutrition (PN) before the onset of cholestasis were comparable between the two groups. There was a trend in the control group to later onset of cholestasis. The patients who received UDCA therapy with doses of 10 to 30 mg/kg/day had a shorter duration of cholestasis than the control group (62.8 vs 92.4 days, P=.006). Furthermore, the peak serum levels of direct bilirubin also was significantly lower in the treatment group.

CONCLUSION

UDCA can improve the course of PNAC in VLBW infants.

Substrate specificities of rat oatp1 and ntcp: implications for hepatic organic anion uptake

Transport of a series of 3H-radiolabeled C23, C24, and C27 bile acid derivatives was compared and contrasted in HeLa cell lines stably transfected with rat Na+/taurocholate cotransporting polypeptide (ntcp) or organic anion transporting polypeptide 1 (oatp1) in which expression was under regulation of a zinc-inducible promoter. Similar uptake patterns were observed for both ntcp and oatp1, except that unconjugated hyodeoxycholate was a substrate of oatp1 but not ntcp. Conjugated bile acids were transported better than nonconjugated bile acids, and the configuration of the hydroxyl groups (alpha or beta) had little influence on uptake. Although cholic and 23 norcholic acids were transported by ntcp and oatp1, other unconjugated bile acids (chenodeoxycholic, ursodeoxycholic) were not. In contrast to ntcp, oatp1-mediated uptake of the trihydroxy bile acids taurocholate and glycocholate was four- to eightfold below that of the corresponding dihydroxy conjugates. Ntcp mediated high affinity, sodium-dependent transport of [35S]sulfobromophthalein with a Km similar to that of oatp1-mediated transport of [35S]sulfobromophthalein (Km = 3.7 vs. 3.3 muM, respectively). In addition, for both transporters, uptake of sulfobromophthalein and taurocholic acid showed mutual competitive inhibition. These results indicate that the substrate specificity of ntcp is considerably broader than previously suspected and caution the extrapolation of transport data obtained in vitro to physiological function in vivo.

Determination of ursodeoxycholic acid in pharmaceutical preparations by capillary electrophoresis with indirect UV detection

A simple and rapid capillary electrophoretic method, with indirect UV detection, for the quantification of ursodeoxycholic acid (UDCA) in pharmaceutical preparations was developed in this study. Sodium p-hydroxy benzoate was used as background electrolyte (BGE) (5 mM, pH 8.0) and visualization agent. Separation was carried out on a fused-silica capillary (50 microm x 72 cm) at a potential of 25 kV under ambient temperature and detected at 250 nm. Glycocholic acid was used as internal standard for quantification. Both run-to-run repeatability and day-to-day reproducibility of migration time were below 0.1% relative standard deviation (R.S.D.). Repeatability and reproducibility of relative peak height were 3.3 and 3.8% R.S.D., respectively. Accuracy was tested by spiking two pharmaceutical tablets with standards and the recoveries were 101.9+/-9.87 and 99.6+/-9.60% (n=3), respectively. Linearity of relative peak height was tested in the range 20-100 microg/ml. Limit of detection (LOD) was 3 microg/ml. The method could be used to assay UDCA raw materials and formulation products.

Increased susceptibility of cholangiocytes to tumor necrosis factor-alpha cytotoxicity after bile duct ligation

Tumor necrosis factor (TNF)-alpha plays a critical role in epithelial cell injury. However, the role of TNF-alpha in mediating cholangiocyte injury under physiological or pathophysiological conditions is unknown. Thus we assessed the effects of TNF-alpha alone or following sensitization by actinomycin D on cell apoptosis, proliferation, and basal and secretin-stimulated ductal secretion in cholangiocytes from normal or bile duct-ligated (BDL) rats. Cholangiocytes from normal or BDL rats were highly resistant to TNF-alpha alone. However, presensitization by actinomycin D increased apoptosis in cholangiocytes following BDL and was associated with an inhibition of proliferation and secretin-stimulated ductal secretion. Thus TNF-alpha mediates cholangiocyte injury and altered ductal secretion following bile duct ligation. These observations suggest that cholestasis may enhance susceptibility to cytokine-mediated cholangiocyte injury.

Nuclear receptors in cholesterol catabolism: molecular biology of the enterohepatic circulation of bile salts and its role in cholesterol homeostasis

Recent advances in bile-salt research have revolutionized thought pertaining to the regulation of cholesterol homeostasis by highlighting the molecular control of reverse cholesterol transport and cholesterol catabolism to bile acids. The latter involves both feed-forward and feedback regulation of bile-acid synthesis within the territory of the enterohepatic circulation of bile salts. Cholesterol is vital to advanced life forms because it has become essential for membrane structure and function and is a precursor to the synthesis of steroid hormones, vitamins A and D, and bile acids. The liver plays a major part in cholesterol metabolism in that it is capable of de novo cholesterol synthesis and uptake from high-density lipoprotein reverse cholesterol transport, low-density lipoprotein, and chylomicron remnant receptors, so that 50% of total body cholesterol is available to be catabolized to bile acids. Cholesterol catabolism to bile acids allows the eukaryote cell to maintain cholesterol homeostasis because it cannot degrade cholesterol's cyclopentanoperhydrophenanthrene ring. Bile-salt catabolic end products of cholesterol must also be regulated to maintain normal bile-acid pool size, secretion, and elimination to avoid bile-salt hepatocyte toxicity. Nuclear hormone receptors, after sensing inappropriate oxysterol and bile-salt levels, are transcription factors that initiate the genetic transactivation to modulate reverse cholesterol transport, cholesterol catabolism, and bile-acid metabolism contiguous to and within the enterohepatic circulation of bile salts so as to regulate cholesterol and bile-salt homeostasis, respectively. This new knowledge should spawn pharmacologic discoveries that modulate nuclear receptors for the treatment of disorders of cholesterol homeostasis.

Utilization of hepatoprotectants within the National Health Insurance in Taiwan

BACKGROUND

Although the hepatoprotectants of Western medicine have centuries of history, their utilization patterns have been seldom documented. Because the National Health Insurance program in Taiwan reimburses hepatoprotectant use, we could estimate the age- and sex-specific prevalence and utilization patterns of hepatoprotectants in Western medicine within the health insurance system in Taiwan.

METHODS

We analyzed the outpatient prescription data of 50000 randomly sampled insured patients in 2000. Only patients using drugs indicated for liver diseases and diagnostic codes related to liver diseases on the same visit were considered to be receiving hepatoprotectants. Drugs involved in Chinese medicine were not included.

RESULTS

Among the valid cohort of 46614 people, 783 (1.7%) were identified as patients with liver disease and receiving hepatoprotectants. Highest prevalence of hepatoprotectant use was 4.9% in the 60-69 years age group. Silymarin, multivitamins, methionine, ursodeoxycholic acid, and liver hydrolysate accounted for 88.8% of the 3215 prescribed items of hepatoprotectants. Patients receiving hepatoprotectants had, on average, visited the clinics more frequently than those not using hepatoprotectants (30 vs 14 times in a year, P < 0.001), and used more insurance benefits (US dollars 1352 vs US dollars 456, P < 0.001).

CONCLUSIONS

The frequency of use of major hepatoprotectants in Taiwan corresponded to the current modalities of treatment under discussion worldwide.

Effect of ursodeoxycholic acid on the impairment induced by maternal cholestasis in the rat placenta-maternal liver tandem excretory pathway

We investigated the effects of ursodeoxycholic acid (UDCA; 60 microg/day/100 g b.wt.) on the impairment induced by maternal obstructive cholestasis during pregnancy (OCP) in the rat placenta-maternal liver tandem excretory pathway. A blunted catheter was implanted in the common bile duct on day 14 of pregnancy, and the tip was cut on day 21. [(14)C]Glycocholate (GC) was then administered through the umbilical artery of "in situ" perfused placenta (placental transfer test) or through the maternal jugular vein (biliary secretion test), and GC bile output was measured. OCP impaired both GC placental transfer and maternal biliary secretion. UDCA moderately improved the latter but had a more marked beneficial effect on GC placental transfer. Histological examination revealed trophoblast atrophy and structural alterations, e.g., loss of apical membrane microvilli in OCP placentas. Gene expression level was investigated by real-time quantitative reverse transcription-polymerase chain reaction and Western blot analysis. OCP reduced both placental lactogen II (a trophoblast-specific gene) mRNA and the functional amount of epithelial tissue, determined by transplacental diffusion of antipyrin. Using a rapid filtration technique, impairment in the ATP-dependent GC transport across trophoblast apical plasma membranes obtained from OCP placentas was found. UDCA partially prevented all these changes. The expression level of organic anion transporters Oatp1, Oatp2, and Oatp4, and multidrug resistance-associated proteins Mrp1, Mrp2, and Mrp3 in whole placenta were not affected or were moderately affected by OCP but greatly enhanced by UDCA. In summary, UDCA partially prevents deleterious effects of OCP on the rat placenta-maternal liver tandem excretory pathway, mainly by preserving trophoblast structure and function.