Ursodeoxycholic acid for treatment of primary sclerosing cholangitis: a placebo-controlled trial

Primary sclerosing cholangitis: diagnosis and management

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease caused by progressive inflammatory destruction of intrahepatic and extrahepatic bile ducts, and ultimately cirrhosis. PSC occurs primarily in patients with underlying ulcerative colitis and affects primarily young to middle-aged men. PSC is believed to be an autoimmune disease mediated by immune dysregulation in patients with genetic susceptibility. One possible mechanism for the development of PSC is the homing of memory lymphocytes to the biliary tract. Cholangiography is the gold standard for diagnosis of PSC. The typical radiologic findings include multifocal strictures and dilation involving the intrahepatic or extrahepatic biliary tract, or both. Although no medical therapy has proved beneficial, a variety of agents have been tested, some of which appear promising and deserve further study. High-dose ursodeoxycholic acid may have benefit in slowing disease progression; a multicenter placebo-controlled trial is ongoing. Liver transplantation is a good option for patients with advanced PSC, although the disease can recur after successful transplantation.

High-dose ursodeoxycholic acid in primary sclerosing cholangitis: a 5-year multicenter, randomized, controlled study

BACKGROUND & AIMS

There is no medical treatment of proven benefit for primary sclerosing cholangitis. This study aimed at studying the effect of a higher dose of ursodeoxycholic acid than previously used on survival, symptoms, biochemistry, and quality of life in this disease.

METHODS

A randomized placebo-controlled study was performed in tertiary and secondary gastroenterology units. A total of 219 patients were randomized to 17 to 23 mg/kg body weight per day of ursodeoxycholic acid (n = 110) or placebo (n = 109) for 5 years. Follow-up data are available from 97 patients randomized to ursodeoxycholic acid and for 101 randomized to placebo. Quality of life was assessed by using the Medical Outcomes Study 36-item Short-Form Health Survey.

RESULTS

The combined end point "death or liver transplantation" occurred in 7 of 97 (7.2%) patients in the ursodeoxycholic acid group vs 11 of 101 (10.9%) patients in the placebo group (P = .368; 95% confidence interval, -12.2% to 4.7%). The occurrence of liver transplantation as a single end point showed a similar positive trend for ursodeoxycholic acid treatment (5/97 [5.2%] vs 8/101 [7.9%]; 95% confidence interval, -10.4% to 4.6%). Three ursodeoxycholic acid and 4 placebo patients died from cholangiocarcinoma, and 1 placebo patient died from liver failure. Alkaline phosphatase and alanine aminotransferase tended to decrease during the first 6 months. There were no differences between the 2 groups in symptoms or quality of life. Analyses of serum ursodeoxycholic acid concentration gave no evidence that noncompliance may have influenced the results.

CONCLUSIONS

This study found no statistically significant beneficial effect of a higher dose of ursodeoxycholic acid than previously used on survival or prevention of cholangiocarcinoma in primary sclerosing cholangitis.

Review article: current management of primary sclerosing cholangitis

The management of primary sclerosing cholangitis (PSC) is hindered by incomplete understanding of the pathogenesis of the disease and the lack of good prognostic models. Few large randomized controlled trials of drug therapy have been published. Best practice in the management of PSC is currently based therefore on careful interpretation of the available evidence, close observation of individual patients and clinical experience of the disease. Drug therapy is useful for alleviating symptoms. Ursodeoxycholic acid may slow progression of the disease and reduce the frequency of complications. Consensus is emerging on the issues of screening for the malignant complications of PSC and the indications for liver transplantation are becoming broader and encompassing the earliest stages of cholangiocarcinoma. In view of the rarity of the disease in the general population, large international collaborations to study PSC are necessary to provide clearer answers in areas of uncertainty, and these are now beginning to emerge.

Treatment of Biliary Problems in Inflammatory Bowel Disease

The most common biliary problem in patients with inflammatory bowel disease is primary sclerosing cholangitis (PSC). The treatment of this disease is multifaceted and frequently requires a multidisciplinary approach involving internists, nutritionists, gastroenterologists, and surgeons. Unfortunately, other than liver transplantation, no therapy that is currently available has been proven to alter the natural history of PSC or prolong survival. Ursodeoxycholic acid is currently the most promising pharmacologic treatment option for slowing disease progression and should be used in higher than usual doses (20 to 30 mg/kg/d). Treatment of symptoms due to cholestasis, such as pruritis and steatorrhea, is an important aspect of the medical care of patients with PSC. Our preferred treatment of pruritis due to cholestasis is with bile acid binding exchange resins such as cholestyramine or colestipol (which is generally better tolerated than cholestyramine). Endoscopic therapy should be reserved for patients with obstructive jaundice, cholangitis, or symptomatic dominant biliary strictures. We recommend dilation of dominant strictures with graduated or balloon dilators followed by temporary stenting if the postdilation cholangiographic appearance is not improved or adequate biliary drainage cannot be assured. There is indirect evidence that the combination of ursodeoxycholic acid and endoscopic therapy to maintain biliary patency may improve transplant-free survival in patients with PSC, although this remains to be proven. Liver transplantation remains the only effective treatment of advanced PSC, and should be considered in patients with complications of cirrhosis or intractable pruritis or fatigue.

Bioequivalence of a new liquid formulation of ursodeoxycholic acid (Ursofalk suspension) and Ursofalk capsules measured by plasma pharmacokinetics and biliary enrichment

BACKGROUND

Ursodeoxycholic acid is an approved therapy for hepatobiliary disorders but in infants and children compliance is compromised because it is formulated exclusively as capsules, or tablets.

AIM

To determine the pharmacokinetics and bioequivalence of a new liquid formulation of ursodeoxycholic acid (Ursofalk suspension) with a standard capsule (Ursofalk) in a randomized, unblinded, crossover designed study of 24 healthy adults.

METHODS

Equivalence was based on single bolus oral plasma pharmacokinetics and biliary ursodeoxycholic acid enrichments after repeat doses. Biliary bile acid composition and hydrophobicity index were also compared. Ursodeoxycholic acid was measured in duodenal bile by high-performance liquid chromatography and in plasma by mass spectrometry.

RESULTS

The mean percentage biliary ursodeoxycholic acid enrichment after administration of the suspension was not significantly different from that obtained with capsules (44.2 +/- 11.7% vs. 46.9 +/- 10.2%, respectively). The equivalence ratio was 0.94 (95% CI: 0.8-1.1), establishing bioequivalence between suspension and capsules. Both formulations reduced the biliary hydrophobicity index and no differences in bile acid composition were observed between formulations. The plasma pharmacokinetics of both formulations was similar and the tolerability of the suspension was excellent.

CONCLUSIONS

A new liquid formulation of ursodeoxycholic acid suitable for paediatric patients is pharmacologically bioequivalent to capsules when given as single, or repeated oral doses.

No relevant effect of ursodeoxycholic acid on cytochrome P450 3A metabolism in primary biliary cirrhosis

Induction of cytochrome P450 3A (CYP3A) has been suggested as a mechanism of action of ursodeoxycholic acid (UDCA) in cholestasis. CYP3A is of key importance in human drug metabolism, being involved in presystemic extraction of more than 50% of all drugs currently available and of various endogenous compounds. Therefore, we compared the induction potential of UDCA with that of the prototypical inducer rifampicin in a human model study with the CYP3A substrates budesonide and cortisol. Twelve patients with early-stage primary biliary cirrhosis and eight healthy volunteers were treated with UDCA (15 mg/kg daily) for 3 weeks and subsequently with rifampicin (600 mg/d) for 1 week. Extensive pharmacokinetic profiling of oral budesonide (3 mg) was performed by determination of budesonide and phase I metabolites (6beta-hydroxybudesonide, 16alpha-hydroxyprednisolone) in plasma and urine at baseline and at the end of each treatment. In parallel, urinary 6beta-hydroxycortisol, a validated marker of CYP3A induction, was determined. UDCA did not affect biotransformation of budesonide and urinary excretion of 6beta-hydroxycortisol either in patients or in healthy volunteers. Ratios of areas under plasma concentration-time curves (AUC(0-12 h) during UDCA/AUC(0-12 h) before UDCA) of both metabolites were not higher than those of budesonide itself. In contrast, administration of rifampicin markedly induced CYP3A metabolism, resulting in abolished budesonide plasma levels and high urinary excretion of 6beta-hydroxycortisol. Metabolite formation was enhanced by rifampicin, but not by UDCA (e.g., AUC(16alpha-hydroxyprednisolone)/AUC(budesonide) in patients: baseline, 8.6 +/- 3.9; UDCA, 10.7 +/- 7.1; rifampicin, 527.0 +/- 248.7). In conclusion, UDCA is not a relevant inducer of CYP3A enzymes in humans.

Ursodeoxycholic acid induced activation of the glucocorticoid receptor in primary rat hepatocytes

BACKGROUND AND AIMS

Ursodeoxycholic acid (UDCA), a hydrophilic bile acid, improves biochemical, immunopathological and histological parameters in chronic cholestatic liver diseases. The immunomodulatory properties of UDCA show interesting similarities with the effects of glucocorticoids. We investigated the activation of the glucocorticoid receptor by UDCA and the glucocorticoid receptor dependent gene expression in primary rat hepatocytes as well as binding of radiolabelled UDCA to the glucocorticoid receptor ligand binding site expressed in a glucocorticoid receptor fusion protein.

METHODS

Primary rat hepatocytes in culture were co-transfected with a luciferase reporter gene construct (GRE-luc) containing a glucocorticoid receptor responsive element (GRE) and a glucocorticoid receptor expression vector (6RGR) followed by stimulation with dexamethasone or UDCA. Luciferase activity was determined and specific binding of glucocorticoid receptor to the GRE was confirmed by an electrophoretic mobility shift assay (EMSA). The glucocorticoid receptor binding site was expressed in a GR-myc fusion protein and binding of radiolabelled UDCA to the fusion protein was determined.

RESULTS

Incubation of co-transfected hepatocytes with 0.1-1.000 microM dexamethasone or 0.1-1.000 microM UDCA led to an 11.9- to 20.85-fold (dexamethasone) and 2.6- to 4.3-fold (UDC) increase of luciferase activity. Mobility shift assays using nuclear extracts from transfected and stimulated hepatocytes also showed a dose dependent increase of DNA binding after stimulation with UDCA. However, incubation of the GR-myc fusion protein with radiolabelled UDCA yielded no specific binding of UDCA to the glucocorticoid receptor binding site, whereas dexamethasone showed specific binding of the fusion protein.

CONCLUSIONS

UDCA activates the intracellular glucocorticoid receptor in a dose-dependent manner. Direct binding of the glucocorticoid receptor by radiolabelled UDCA at the glucocorticoid receptor binding site could be excluded as the mechanism of activation. The mechanisms involved in UDCA-mediated glucocorticoid receptor activation and possible targeted glucocorticoid receptor activation due to partial UDCA tissue specificity warrant further elucidation.

Mycophenolate mofetil for the treatment of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown etiology. Despite advances in understanding the pathophysiology underlying this disorder, no effective medical therapy has been identified for halting disease progression. The aim of this investigation was to determine the safety and estimated efficacy of mycophenolate mofetil (MMF) for the treatment of PSC. Thirty patients with PSC received MMF 1 g daily to a maximum of 3 g daily for 1 yr. Liver tests were determined at 3-month intervals with the Mayo risk score calculated at baseline and at the end of therapy. Twenty-three (77%) patients completed 1 yr of therapy. Significant but clinically marginal improvement in serum alkaline phosphatase level after 1 yr of therapy was observed (1135 +/- 581 U/L vs 912 +/- 463 U/L, p= 0.02). No other significant changes in liver biochemistries or Mayo risk score was observed. Seven patients (23%) discontinued MMF due to adverse events possibly related to therapy. Adverse reactions resolved spontaneously or with dose reduction in 10 (33%) patients. One patient developed pancreatitis, bacterial cholangitis, and sepsis during the eighth month of MMF therapy. No patient developed cytopenia on therapy. In conclusion, MMF does not appear to have clinically important benefits for PSC despite being tolerated by most patients. The results of this pilot study do not support further study of MMF as a single agent in the treatment of PSC.

Primary sclerosing cholangitis: Updates in diagnosis and therapy

Primary sclerosing cholangitis (PSC) is a chronic cholestatic syndrome of unknown origin mostly found in males, and characterized by diffuse inflammation and fibrosis of both intra- and extra-hepatic bile ducts. So far, PSC is considered as an autoimmune hepatobiliary disease. In most cases the progression of PSC towards liver cirrhosis and liver failure is slow but irreversible, and liver transplantation is currently the only definitive treatment. In recent years, PSC has been an area of active research worldwide with great interest in etiology, pathogenesis, diagnosis, and therapeutic options such as hydrophilic ursodeoxycholic acid and immunosuppressive agent tacrolimus. Recent updates on clinical and therapeutic aspects of PSC are discussed in the present review.

Primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease characterized by inflammation and fibrosis of the intra- and extrahepatic bile ducts. An estimated 80% of patients in North America and Europe have coexistent inflammatory bowel disease (IBD). The underlying pathophysiology of PSC remains poorly understood. As a result, there is currently no effective medical therapy to halt disease progression. Important complications from PSC include metabolic bone disease, colorectal neoplasia, and cholangiocarcinoma. Liver transplantation remains the only successful treatment option for patients with advanced liver disease from PSC. A diagnosis of PSC should be considered among individuals with IBD and elevated serum liver biochemical tests.

Ursodiol Use Is Possibly Associated with Lower Incidence of Hepatocellular Carcinoma in Hepatitis C Virus–Associated Liver Cirrhosis

In a previous study of patients with hepatitis C virus (HCV)–associated liver cirrhosis (HCV-LC), we showed that increased liver inflammation, as assessed by higher serum alanine aminotransferase (ALT), was associated with increased risk for the development of hepatocellular carcinoma (HCC). This suggested that suppression of inflammation might inhibit HCC development in HCV-LC. Several agents have been suggested to possess chemopreventive potential against the development of HCC in chronic HCV-associated liver disease, including herbal medicines, such as Stronger-Neo-Minophagen C (glycyrrhizin) and Sho-saiko-to (TJ-9). Ursodiol [ursodeoxycholic acid (UDCA)], a bile acid widely used to treat cholestatic liver diseases, also possesses anti-inflammatory properties in liver disease. We hypothesized that suppression of liver inflammation, as assessed by decreases in serum ALT, might inhibit HCC occurrence in patients with HCV-LC. In this study, the preventive effect of UDCA on HCC was examined in patients with early-stage HCV-LC. One hundred two patients with HCV-LC (Child stage A) were treated with anti-inflammatory drugs, Stronger-Neo-Minophagen C,Sho-saiko-to, or UDCA, with the goal of lowering the average serum ALT level to <80 IU. Iftheaverage ALT level did not remain <80 IU after treatment with one agent, multiagent therapy was initiated. The patients were followed up for >5 years and were retrospectively subdivided into two groups: 56 UDCA users (group A) and 46 UDCA nonusers (group B). The mean ± SD dosage of UDCA administered in group A was 473.7 ± 183.0 mg/d. The average duration of UDCA administration in group A was 37.3 ± 15.9 months over the 5-year study period. The cumulative incidence of HCC was recorded. The 5-year incidence of HCC in group A was 17.9% (10 of 56) and was significantly lower than that in group B (39.1%, 18 of 46; P = 0.025). The risk for HCC incidence, calculated by a logistic regression model, showed that the administration of UDCA significantly decreased hepatocarcinogenesis (P = 0.036). The herbal medicines used were comparable in dosage and treatment duration in the UDCA and non-UDCA groups. In conclusion, UDCA might prevent HCC development in HCV-LC. Interestingly, because the serum ALT trends over time were nearly the same in both groups, the chemopreventive effectiveness of UDCA was not accompanied by greater reductions in ALT compared with the UDCA nonusers.

Metronidazole and ursodeoxycholic acid for primary sclerosing cholangitis: a randomized placebo-controlled trial

No effective medical therapy is currently available for primary sclerosing cholangitis (PSC). Ursodeoxycholic acid (UDCA) improves liver enzymes, but its effect on liver histology is controversial. Metronidazole (MTZ) prevents PSC-like liver damage in animal models and reduces intestinal permeability. We recruited 80 patients with PSC into a randomized placebo-controlled study to evaluate the effect of UDCA and MTZ (UDCA/MTZ) compared with UDCA/placebo on the progression of PSC. Patients (41 UDCA/placebo and 39 UDCA/MTZ) were followed every third month. Assessment of liver function test, histological stage and grade, and cholangiography (via ERCP) at baseline showed no differences between the groups. After 36 months, serum aminotransferases gamma-glutamyltransferase, and alkaline phosphatase (ALP) decreased markedly in both groups, serum ALP more significantly in the UDCA/MTZ group (-337 +/- 54 U/L, P < .05) compared with the UDCA/placebo group. The New Mayo Risk Score decreased markedly only in the UDCA/MTZ group (-0.50 +/- 0.13, P < .01). The number of patients with improvement of stage (P < .05) and grade (P < .05) was higher in the combination group. ERCP findings showed no progression or improvement in 77% and 68% of patients on UDCA/MTZ and UDCA/placebo, respectively. In conclusion, combining MTZ with UDCA in PSC improved serum ALP levels and New Mayo Risk Score, but no statistically significant effect on disease progression as assessed via liver histology or ERCP was seen. Long-term studies using a higher dose of UDCA combined with MTZ in larger patient populations are indicated.

A prospective, randomized-controlled pilot study of ursodeoxycholic acid combined with mycophenolate mofetil in the treatment of primary sclerosing cholangitis

BACKGROUND

Ursodeoxycholic acid has been ineffective in the treatment of primary sclerosing cholangitis. Because the pathogenesis of primary sclerosing cholangitis is related to immune destruction of bile duct epithelium, several immune suppressive agents have been evaluated. Mycophenolate mofetil is a potent immunosuppressant that is now widely used in organ transplantation.

AIM

In this pilot study to determine if mycophenolate mofetil when combined with ursodeoxycholic acid could prevent evidence of clinical progression and improve the biochemical, histological and/or cholangiographic features of primary sclerosing cholangitis compared with patients treated with ursodeoxycholic acid alone.

METHODS

Twenty-five patients with well-defined primary sclerosing cholangitis were randomized to ursodeoxycholic acid (13-15 mg/kg/day) with or without mycophenolate mofetil (1000 mg b.d.). Cholangiography and liver biopsy were performed at study entry and after 2 years of treatment. Symptoms, clinical features of liver disease and biochemical tests were monitored at 3-month intervals.

RESULTS

The mean age 44 years, 58% male, 84% Caucasian and 64% had ulcerative colitis. After 2 years, there were no differences in laboratory values, histological stage or cholangiograms between patients treated with ursodeoxycholic acid alone and those treated with mycophenolate mofetil + ursodeoxycholic acid.

CONCLUSIONS

Mycophenolate mofetil combined with ursodeoxycholic acid does not appear to provide additional benefit compared with standard doses of ursodeoxycholic acid alone in the treatment of primary sclerosing cholangitis.

Effect of high-dose ursodeoxycholic acid on its biliary enrichment in primary sclerosing cholangitis

Ursodeoxycholic acid (UDCA) has beneficial effects in cholestatic liver diseases. In primary sclerosing cholangitis (PSC), there is evidence that high doses (+/- 20 mg/kg) of UDCA may be more effective than average doses. Biliary enrichment of UDCA at such high doses may represent the decisive factor for its beneficial effect. Up to now it is not clear how high-dose UDCA correlates with its biliary enrichment and whether bacterial degradation of large amounts of UDCA may lead to an increased bacterial formation of more toxic hydrophobic bile acids. We determined the biliary bile acid composition in 56 patients with PSC including 30 patients with repeat bile samples treated with various doses of UDCA. At a UDCA dose of 10-13 mg/kg/d (n = 18) biliary UDCA represented 43.1% + 0.3% (mean + SD) of total bile acids; at a UDCA dose of 14-17 mg/kg (n = 14), its biliary content increased to 46.9% + 0.3%, at 18-21 mg/kg (n = 34) to 55.9% + 0.2%, at 22-25 mg/kg (n = 12) to 58.6% + 2.3%, and at 26-32 mg/kg (n = 8) to 57.7% + 0.4%. During UDCA treatment, the biliary content of all other bile acids was unchanged or decreased. In conclusion, biliary enrichment of UDCA increases with increasing dose and reaches a plateau at 22-25 mg/kg. There was no increase of toxic hydrophobic bile acids. If biliary enrichment of UDCA represents the decisive factor for its clinical effect, it seems likely that UDCA doses of up to 22-25 mg/kg may be more effective than lower doses.

Primary sclerosing cholangitis

Primary sclerosing cholangitis is a cholestatic liver disease strongly associated with IBD. Considerable advances in the understanding of its pathogenesis have been made. The idea of autoimmunity affecting genetically susceptible individuals is largely accepted; however, much remains to be explained about the origin of this disease. Despite active investigation of different therapeutic modalities with the goal of modifying disease progression, liver transplantation continues to be the only option to provide survival benefit in these patients.

Mechanisms of action and therapeutic efficacy of ursodeoxycholic acid in cholestatic liver disease

Ursodeoxycholic acid (UDCA) is widely used for the treatment of cholestatic liver diseases. Multiple mechanisms of action of UDCA have been described aiming at one or more of the pathogenetic processes of cholestatic liver diseases: (1) protection of injured cholangiocytes against toxic effects of bile acids, (2) stimulation of impaired biliary secretion, (3) stimulation of detoxification of hydrophobic bile acids, and (4) inhibition of apoptosis of hepatocytes. Through one or more of these mechanisms, UDCA slows the progression of primary biliary cirrhosis and improves a number of other cholestatic disorders.

Protective effects of ursodeoxycholic acid against 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced testicular damage in mice

The protective effect of ursodeoxycholic acid (UDCA), a biliary component found in bears, on 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced testicular damage in mice was investigated. Fifty C57BL/6J mice were equally divided into five groups. The mice in the control group received the vehicle and standard chow. The single TCDD treatment group received 27.5 microg/kg of TCDD subcutaneously. The UDCA-included treatment group received pulverized chow containing 0.125%, 0.25% and 0.5% UDCA, respectively, for 70 days starting 10 days before TCDD injections. The body and testicular weights were shown to be decreased in the single TCDD treatment group, while the decrease was prevented by UDCA added to the chow. In addition, the decrease in the serum-luteinizing hormone (LH) or the follicle stimulating hormone (FSH) secondary to a TCDD injection was not observed in the UDCA-included treatment group. Contrary to the single TCDD treatment group, the germinal epithelium and intercellular space were relatively well preserved in the UDCA-included treatment group. Adding UDCA also normalized TCDD-induced irregular ultrastructural changes such as development of phagolysosomes, inflated smooth endoplasmic reticulum (SER), dilated and altered mitochondria, necrosis and completely damaged seminiferous tubules. Moreover, in the experiment for Arnt expression, UDCA added to the chow suppressed the TCDD-induced relocation of Arnt from the cytoplasm to the nuclei. In conclusion, TCDD-induced testicular toxicity was effectively protected by UDCA. There was almost complete recovery of the testes in the UDCA-included treatment group. Thus, UDCA may be useful for the prevention and treatment of TCDD-induced testicular damage.

Inhibition of bile salt-induced apoptosis by cyclic AMP involves serine/threonine phosphorylation of CD95

BACKGROUND AND AIMS

Cyclic AMP (cAMP) inhibits bile salt-induced hepatocyte apoptosis; the underlying mechanisms are unclear.

METHODS

The effects of cAMP on taurolithocholate-3-sulfate-(TLCS)- or glycochenodesoxycholate (GCDC)-induced CD95 (Fas/APO-1) activation and apoptosis were studied in 24-hour cultured rat hepatocytes and in perfused rat liver.

RESULTS

TLCS induced a rapid oxidative stress response, c-Jun-N-terminal kinase (JNK) and epidermal growth factor (EGF) receptor (EGF-R) activation, subsequent EGF-R/CD95 association and CD95 tyrosine phosphorylation, CD95 membrane targeting, death-inducing signal complex (DISC) formation and hepatocyte apoptosis. None of these responses was triggered by cAMP; however, cAMP induced H89-sensitive serine/threonine phosphorylation of CD95. Similar data were obtained with GCDC, another proapoptotic bile acid. cAMP did not prevent the TLCS-induced oxidative stress response, JNK activation and EGF-R/CD95 association, however abolished EGF-R activation and subsequent CD95 tyrosine phosphorylation, CD95 membrane trafficking, and DISC formation in a H89-sensitive way. Also in presence of TLCS, cAMP induced rapid Ser/Thr phosphorylation of CD95 within 10 min. The effects of cAMP on the various steps of CD95 activation were also found in the intact perfused rat liver. Evidence is given that a cAMP-induced Ser/Thr phosphorylation favors internalization of CD95.

CONCLUSIONS

Inhibition of bile salt-induced apoptosis by cAMP involves both PKA-dependent Ser/Thr phosphorylation of the CD95 and inhibition of EGF-R activation, which results in an inhibition of CD95 tyrosine phosphorylation, CD95 membrane targeting, and DISC formation. CD95 regulation involves complex phosphorylations with CD95-tyrosine phosphorylation favoring CD95 membrane trafficking and DISC formation, whereas CD95 Ser/Thr phosphorylation inhibits these processes.

Systematic review: ursodeoxycholic acid--adverse effects and drug interactions

BACKGROUND

Ursodeoxycholic acid is increasingly being used for the treatment of chronic cholestatic liver diseases. It appears to be generally well tolerated, but a systematic review on drug safety is lacking.

AIM

As experimental data suggest a role of bile acids in the regulation of hepatic drug metabolism at both the transcriptional and post-transcriptional level, the literature was screened for adverse drug reactions and drug interactions related to ursodeoxycholic acid.

METHODS

A systematic review of the literature was performed using a refined search strategy to evaluate the adverse effects of ursodeoxycholic acid and its interactions with other drugs.

RESULTS

Ursodeoxycholic acid caused diarrhoea in a small proportion of patients. Rare skin reactions were due to drug adjuvants rather than the active substance. Decompensation of liver cirrhosis was reported after the administration of ursodeoxycholic acid in single cases of end-stage primary biliary cirrhosis. Recurrent right upper quadrant abdominal pain was incidentally observed. The absorption of ursodeoxycholic acid was impaired by colestyramine, colestimide, colestipol, aluminium hydroxide and smectite. Metabolic drug interactions were reported for the cytochrome P4503A substrates, ciclosporin, nitrendipine and dapsone.

CONCLUSIONS

Ursodeoxycholic acid is generally well tolerated. Drug absorption interactions with anion exchange resins deserve consideration. Metabolic interactions with compounds metabolized by cytochrome P4503A are to be expected.

Loss of inositol 1,4,5-trisphosphate receptors from bile duct epithelia is a common event in cholestasis

BACKGROUND AND AIMS

Cholestasis is one of the principal manifestations of liver disease and often results from disorders involving bile duct epithelia rather than hepatocytes. A range of disorders affects biliary epithelia, and no unifying pathophysiologic event in these cells has been identified as the cause of cholestasis. Here we examined the role of the inositol 1,4,5-trisphosphate receptor (InsP3R)/Ca(2+) release channel in Ca(2+) signaling and ductular secretion in animal models of cholestasis and in patients with cholestatic disorders.

METHODS

The expression and distribution of the InsP3R and related proteins were examined in rat cholangiocytes before and after bile duct ligation or treatment with endotoxin. Ca(2+) signaling was examined in isolated bile ducts from these animals, whereas ductular bicarbonate secretion was examined in isolated perfused livers. Confocal immunofluorescence was used to examine cholangiocyte InsP3R expression in human liver biopsy specimens.

RESULTS

Expression of the InsP3R was selectively lost from biliary epithelia after bile duct ligation or endotoxin treatment. As a result, Ca(2+) signaling and Ca(2+)-mediated bicarbonate secretion were lost as well, although other components of the Ca(2+) signaling pathway and adenosine 3',5'-cyclic monophosphate (cAMP)-mediated bicarbonate secretion both were preserved. Examination of human liver biopsy specimens showed that InsP3Rs also were lost from bile duct epithelia in a range of human cholestatic disorders, although InsP3R expression was intact in noncholestatic liver disease.

CONCLUSIONS

InsP3-mediated Ca(2+) signaling in bile duct epithelia appears to be important for normal bile secretion in the liver, and loss of InsP3Rs may be a final common pathway for cholestasis.

Circulating soluble cytochrome c in liver disease as a marker of apoptosis

OBJECTIVES

To measure levels of soluble cytochrome c, a clinical marker of apoptosis in patients with liver disease; determine whether soluble cytochrome c is derived from the liver; and correlate soluble cytochrome c level with histology and disease activity.

DESIGN

Laboratory research study with comparison group.

SETTING

Liver Institute, at the Rabin Medical Center, Israel, and In Vitro Toxicology Laboratory, Canada.

SUBJECTS

A total of 108 patients with liver disease and 30 healthy controls.

INTERVENTIONS

Paired hepatic and portal vein samples were taken via the transjugular vein in patients after liver biopsy and transjugular intrahepatic portacaval shunt, and bile from patients with external biliary drainage. Soluble cytochrome c was measured with an enzyme-linked immunosorbent assay in peripheral blood. Apoptotic cells in liver tissue were identified by morphological criteria and quantitated with the dUTP nick-end-labelling (TUNEL) assay.

MAIN OUTCOME MEASURES

Soluble cytochrome c level by type of liver disease by clinical and histological findings.

RESULTS

Soluble cytochrome c concentration (mean 187.1 +/- 219.5 ng x mL(-1)) was significantly higher in patients with liver disease than in controls (39.8 +/- 35.1 ng x mL(-1); P = 0.0001), with highest levels in the primary sclerosing cholangitis group (mean 1041.0 +/- 2844.8 ng x mL(-1); P = 0.001). Cytochrome c levels were correlated with serum bilirubin, alkaline phosphatase, creatinine levels, necroinflammatory score and apoptotic index, but not with serum alanine aminotransferase and synthetic liver function tests. In the 16 paired samples, soluble cytochrome c level was higher in the hepatic (mean 267.9 +/- 297.0 ng x mL(-1)) than the portal vein (mean 169.2 +/- 143.3 ng x mL(-1)), and it was highly detectable in bile (mean 2288.0 +/-4596.0 ng x mL(-1)) (P = 0.001). Untreated patients with chronic viral hepatitis (B and C) had significantly higher levels (mean 282.8 +/-304.3 ng x mL(-1)) than treated patients (77.9 +/- 35.8 ng x mL(-1); P = 0.001).

CONCLUSIONS

Soluble cytochrome c levels are increased in different types of liver disease. Soluble cytochrome c is probably derived from the liver and secreted into the bile. Levels correlate with the apoptotic index and are affected by antiviral treatment. Soluble cytochrome c may serve as a serum marker of apoptosis.

Pharmacokinetics and pharmacodynamic action of budesonide in early- and late-stage primary biliary cirrhosis

Budesonide has been discussed as a potential treatment option in primary biliary cirrhosis (PBC). Therefore, we studied the pharmacokinetics and pharmacodynamics of budesonide in patients with PBC stage I/II and stage IV. Twelve patients with early PBC stage I/II and 7 patients with PBC stage IV under continuous treatment with ursodeoxycholic acid (UDCA) were enrolled in an exploratory trial. Each patient received oral budesonide for 3 weeks at weekly increasing dosages of 3 mg once to thrice per day. Budesonide and cortisol plasma levels, urinary cortisol excretion, serum liver tests, and immunoglobulins were determined on days 1, 7, and 21 of the study. Patients with PBC stage IV showed significantly higher peak plasma concentrations (4.9 +/- 3.5 vs. 1.5 +/- 0.4 ng/mL; P <.05) and areas under the plasma concentration-time curves (AUC) (23.2 +/- 16.8 vs. 5.1 +/- 1.4 hours. ng/mL, P <.01, total AUC extrapolated to infinity [AUC(0- infinity )]) after a single dose of 3 mg budesonide when compared with patients with PBC stage I/II. Equally, AUC of budesonide were significantly increased under a multiple dose regimen on day 21 (14.0 +/- 11.6 vs. 5.0 +/- 1.9 hours. ng/mL, P <.01, AUC at steady state from dosing time to 8 hours [AUC(ss,0-8 h)]). Higher levels of budesonide were related to a significant decrease in plasma cortisol and reduction of urinary cortisol excretion in patients with stage IV disease. Two patients with stage IV disease developed portal vein thrombosis (PVT). In conclusion, administration of budesonide leads to markedly elevated plasma levels in cirrhotic patients with PBC associated with serious adverse drug reactions. Thus, further evaluation of combined treatment with UDCA may be considered in early-stage PBC but not in cirrhotic patients with PBC.

A randomized double-blind study of the short-time treatment of obese patients with nonalcoholic fatty liver disease with ursodeoxycholic acid

In order to determine the effect of ursodeoxycholic acid on nonalcoholic fatty liver disease, 30 patients with body mass indices higher than 25, serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) or gamma-glutamyltransferase (gamma-GT) at least more than 1.5 times the upper limit of normality, and hepatic steatosis demonstrated by ultrasonography were randomized into two groups of 15 patients to receive placebo or 10 mg kg-1 day-1 ursodeoxycholic acid for three months. Abdominal computed tomography was performed to quantify hepatic fat content, which was significantly correlated with histological grading of steatosis (r s = -0.83, P < 0.01). Patient body mass index remained stable for both groups throughout the study, but a significant reduction in mean ( +/- SEM) serum levels of ALT, AST and gamma-GT was observed only in the treated group (ALT = 81.2 +/- 9.7, 44.8 +/- 7.7, 48.1 +/- 7.7 and 52.2 +/- 6.3 IU/l at the beginning and after the first, second and third months, respectively, N = 14, P < 0.05). For the placebo group ALT values were 66.4 +/- 9.8, 54.5 +/- 7, 60 +/- 7.6 and 43.7 5 IU/l, respectively. No alterations in hepatic lipid content were observed in these patients by computed tomography examination (50.2 +/- 4.2 Hounsfield units (HU) at the beginning versus 51.1 +/- 4.1 HU at the third month). These results show that ursodeoxycholic acid is able to reduce serum levels of hepatic enzymes in patients with nonalcoholic fatty liver disease, but this effect is not related to modifications in liver fat content.

Treatment of primary sclerosing cholangitis with low-dose ursodeoxycholic acid: results of a retrospective Italian multicentre survey

BACKGROUND

Data concerning the usefulness and type of drugs employed to treat patients with primary sclerosing cholangitis are controversial. Ursodeoxycholic acid has been shown to be a useful agent, however the drug dosage and its effect on the clinical course are still under debate.

AIM

To evaluate the efficacy of low-dose ursodeoxycholic acid in the treatment of primary sclerosing cholangitis.

METHODS

We retrospectively analysed data from 86 patients with primary sclerosing cholangitis from eight centres in Italy between 1987 and 1997: 69 were treated with ursodeoxycholic acid (8-13 mg/kg/day), while 17 received symptomatic treatment and served as controls. The effect of therapy was evaluated by standard liver function tests and symptom analysis.

RESULTS

Ursodeoxycholic acid treatment was associated with significant improvement in serum alkaline phosphatase (735+/-833 vs. 519+/-448 U/l, p<0.001), gamma-glutamyl transpeptidase (401+/-352 vs. 234+/-235 U/l, p<0.001), aspartate aminotransferase (87+/-70 vs. 56+/-42 U/l, p=0.001), alanine aminotransferase (146+/-139 vs. 76+/-73 U/l, p<0.001), and total bilirubin (1.88+/-2.44 vs. 1.76+/-4.12 U/l, p=0.01); there was also amelioration of fatigue (p=0.007), jaundice (p=0.002), and body weight loss (p=0.002).

CONCLUSIONS

Ursodeoxycholic acid, at a dose of 8-13 mg/kg/day was beneficial for the general condition and liver biochemistry of patients with primary sclerosing cholangitis; high-dose ursodeoxycholic acid treatment requires further evaluation.

Involvement of integrins and Src in tauroursodeoxycholate-induced and swelling-induced choleresis

BACKGROUND & AIMS

Stimulation of canalicular secretion by tauroursodeoxycholate (TUDC) involves dual activation of p38 mitogen-activated protein kinase (p38(MAPK)) and extracellular signal-regulated kinase (ERK). This study investigates the sensing and upstream signaling events of TUDC-induced choleresis.

METHODS

TUDC and hypo-osmolarity effects on protein kinase activities and taurocholate excretion were studied in perfused rat liver.

RESULTS

TUDC induced a rapid activation of focal adhesion kinase (FAK) and Src, as shown by an increase in Y418 phosphorylation and a decrease in Y529 phosphorylation of Src. Inhibition of Src by PP-2 abolished the TUDC-induced activation of p38(MAPK) but not of FAK and ERKs. An integrin-inhibitory peptide with an RGD motif blocked TUDC-induced FAK, Src, ERK, and p38(MAPK) activation, suggesting that integrin signaling toward FAK/Src is required for TUDC-induced MAPK activation. The RGD peptide and PP-2 also abolished the stimulation of taurocholate excretion in perfused rat liver in response to TUDC. Integrin-dependent Src activation was also identified as an upstream event in hypo-osmotic signaling toward MAPKs and choleresis.

CONCLUSIONS

TUDC-induced stimulation of canalicular taurocholate excretion involves integrin sensing, FAK, and Src activation as upstream events for dual MAPK activation. Integrins may also represent one long-searched sensor for cell hydration changes in response to hypo-osmolarity.

The management of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a chronic cholestatic hepatobiliary disease that usually progresses to biliary cirrhosis and liver failure; it also predisposes to cholangiocarcinoma. The cause of PSC is unknown, although evidence suggests that the tissue damage is mediated by the immune system. There is an unexplained close association between PSC and inflammatory bowel disease, particularly in ulcerative colitis, which coexists in the majority of patients with PSC. No medical therapy has been proven to halt or reverse disease progression; however, recent preliminary evidence suggests that ursodeoxycholic acid (UDCA) in a high dose of 20 to 25 mg/kg may slow the disease process. Evidence from a pilot study suggests that the combination of UDCA and immunosuppressive therapy, such as prednisolone or azathioprine, may also increase efficacy. For patients with end-stage PSC, liver transplantation remains the only effective therapy, although there is clear evidence that PSC may recur in the liver allograft.

Bile acids for primary sclerosing cholangitis

BACKGROUND

Bile acids have been used for treating primary sclerosing cholangitis, but their beneficial and harmful effects remain unclear.

OBJECTIVES

To assess the beneficial and harmful effects of bile acids for patients with primary sclerosing cholangitis.

SEARCH STRATEGY

We searched The Cochrane Hepato-Biliary Group's Trials Register, The Cochrane Library, MEDLINE, EMBASE, and The Chinese Biomedical Database generally from inception through to May 2002.

SELECTION CRITERIA

Randomised clinical trials comparing any dose or duration of bile acids versus placebo, no intervention, or another intervention were included. Trials were included irrespective of blinding, language, or publication status.

DATA COLLECTION AND ANALYSIS

Two reviewers extracted the data. The methodological quality of the trials was evaluated with respect to the generation of the allocation sequence, allocation concealment, double blinding, and follow-up. The results were reported by intention-to-treat analysis. The outcomes were presented as relative risks (RR) or weighted mean differences (WMD), both with 95% confidence intervals (CI).

MAIN RESULTS

We identified six randomised clinical trials, all with low methodological quality. Patients were treated for three months to six years (median two years). Five trials (183 patients) compared ursodeoxycholic acid versus placebo, and one trial (40 patients) compared ursodeoxycholic acid versus no treatment. Ursodeoxycholic acid did not significantly reduce the risk of death (RR 0.86; 95% CI 0.27 to 2.73); treatment failure including liver transplantation, varices, ascites, and encephalopathy (RR 0.94; 95% CI 0.63 to 1.42); liver histological deterioration (RR 0.89; 95% CI 0.45 to 1.74); or liver cholangiographic deterioration (RR 0.43; 95% CI 0.18 to 1.02). Ursodeoxycholic acid significantly improved serum bilirubin (WMD -14.6 micro mol/litre; 95% CI -18.7 to -10.6), alkaline phosphatases (WMD -506 IU/litre; 95% CI -583 to -430), aspartate aminotransferase (WMD -46 IU/litre; 95% CI -77 to -16), and gamma-glutamyltranspeptidase (WMD -260 IU/litre; 95% CI -315 to -205), but not albumin (WMD -0.20 g/litre; 95% CI -1.91 to 1.50). Ursodeoxycholic acid was well tolerated.

REVIEWER'S CONCLUSIONS

Ursodeoxycholic acid leads to a significant improvement in liver biochemistry, but there is insufficient evidence to either support or refute its clinical effects in patients with primary sclerosing cholangitis. Large scale, high-quality randomised clinical trials are needed.

Hepatic graft-versus-host disease resembling acute hepatitis: additional treatment with ursodeoxycholic acid

Hepatic graft-versus-host disease (GVHD) is a frequent complication after bone-marrow transplantation (BMT). The disease is often refractory to immunosuppressive therapy. We present a 30-year-old Japanese male, who developed an abrupt elevation of aminotransferases, on day 135 after allogeneic BMT. A liver biopsy specimen revealed degeneration of the small bile ducts and portal fibrosis, and the diagnosis of chronic hepatic GVHD was confirmed. No manifestation of chronic GVHD was observed except liver dysfunction. The administration of prednisolone (PSL) and cyclosporin (CsA) ameliorated laboratory data to a degree, but they did not return to normal. Treatment with ursodeoxycholic acid (UDCA), subsequently added to the immunosuppressive therapy, apparently normalized the levels of biliary tract enzyme and total bilirubin. His liver function test completely returned to normal on day 260. We believe that it is worthwhile to administer UDCA as an additional treatment for not only common hepatic GVHD but also atypical cases presenting as acute hepatitis.

Prevention of bile acid-induced apoptosis by betaine in rat liver

Bile acid-induced apoptosis plays an important role in the pathogenesis of cholestatic liver disease, and its prevention is of therapeutic interest. The effects of betaine were studied on taurolithocholate 3-sulfate (TLCS) and glycochenodeoxycholate (GCDC)-induced apoptosis in rat hepatocytes in vitro and in vivo. Hepatocyte apoptosis, caspase activation, and poly (ADP-ribose) polymerase (PARP) cleavage, which are normally observed in response to both bile acids, were largely prevented after preincubation of hepatocytes with betaine. Betaine uptake was required for this protective effect, which was already observed at betaine concentrations of 1 mmol/L. Betaine did not affect the TLCS-induced membrane trafficking of CD95 and tumor necrosis factor-related apoptosis inducing ligand (TRAIL) receptor 2 to the plasma membrane or the TLCS-induced recruitment of Fas-associated death domain (FADD) and caspase 8 to the CD95 receptor. However, betaine largely prevented cytochrome c release and oxidative stress exerted otherwise by TLCS. Inhibition of caspase 9 strongly blunted TLCS-induced caspase-8 activation. Further betaine did not prevent the TLCS-induced c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (Erk), and p38 mitogen-activated protein kinase (p38(MAPK)) activation or TLCS-induced protein kinase B (PKB) dephosphorylation. The protective betaine effect was insensitive to inhibition of Erks by PD089059, of p38(MAPK) by SB203580, or of phosphatidylinositol 3-kinase (PI3-kinase) by LY294002. Betaine supplementation in the drinking water significantly ameliorated in vivo hepatocyte apoptosis following bile duct ligation. In conclusion, this study identifies betaine as a potent protectant against bile acid-induced apoptosis in vivo and in vitro, and its antiapoptotic action largely resides on an inhibition of the proapoptotic mitochondrial pathway.

Investigational pharmacologic treatment for liver disease

Liver disease can cause significant morbidity and mortality. Few pharmacological options exist for these diseases, however, new agents are in development and older agents are being evaluated for new indications. Several new nucleoside and nucleotide analogues are being developed to treat hepatitis B virus infection. Pegylated interferons have been developed for hepatitis C infection. Ursodeoxycholic acid has recently been implicated in the treatment of liver disease, including non-alcoholic steatohepatitis and primary sclerosing cholangitis.

Ursodeoxycholic acid in cholestatic liver disease: mechanisms of action and therapeutic use revisited

Ursodeoxycholic acid (UCDA) is increasingly used for the treatment of cholestatic liver diseases. Experimental evidence suggests three major mechanisms of action: (1) protection of cholangiocytes against cytotoxicity of hydrophobic bile acids, resulting from modulation of the composition of mixed phospholipid-rich micelles, reduction of bile acid cytotoxicity of bile and, possibly, decrease of the concentration of hydrophobic bile acids in the cholangiocytes; (2) stimulation of hepatobiliary secretion, putatively via Ca(2+)- and protein kinase C-alpha-dependent mechanisms and/or activation of p38(MAPK) and extracellular signal-regulated kinases (Erk) resulting in insertion of transporter molecules (e.g., bile salt export pump, BSEP, and conjugate export pump, MRP2) into the canalicular membrane of the hepatocyte and, possibly, activation of inserted carriers; (3) protection of hepatocytes against bile acid-induced apoptosis, involving inhibition of mitochondrial membrane permeability transition (MMPT), and possibly, stimulation of a survival pathway. In primary biliary cirrhosis, UDCA (13-15 mg/kg/d) improves serum liver chemistries, may delay disease progression to severe fibrosis or cirrhosis, and may prolong transplant-free survival. In primary sclerosing cholangitis, UDCA (13-20 mg/kg/d) improves serum liver chemistries and surrogate markers of prognosis, but effects on disease progression must be further evaluated. Anticholestatic effects of UDCA have also been reported in intrahepatic cholestasis of pregnancy, liver disease of cystic fibrosis, progressive familial intrahepatic cholestasis, and chronic graft-versus-host disease. Future efforts will focus on definition of additional clinical uses of UDCA, on optimized dosage regimens, as well as on further elucidation of mechanisms of action of UDCA at the molecular level.

Intestinal absorption and biliary secretion of ursodeoxycholic acid and its taurine conjugate

BACKGROUND

Ursodeoxycholic acid (UDCA) and its taurine conjugate (TUDCA) exert a protective effect in cholestatic liver diseases. A greater hepatoprotective effect of TUDCA has been suggested. Absorption appears to be a limiting factor and up to now has not been studied in man.

METHODS

We studied absorption and biliary bile acid secretion and composition after administration of UDCA and TUDCA in patients who had complete extrahepatic biliary obstruction caused by pancreatic carcinoma but had no intestinal or liver disease. After 5 days of intact enterohepatic circulation eight patients with a percutaneous biliary-duodenal drainage received, during two study periods, 1000 mg (1916.9 micromol; mean 29.6 micromol kg(-1)) TUDCA and 750 mg (1910.4 micromol; mean 29.5 micromol kg(-1)) UDCA in random order. Each patient served as his own control.

RESULTS

After UDCA and TUDCA administration the biliary UDCA content increased to 55.2% and 54.6% of total bile acids, respectively (not significant). Biliary secretion of cholic and chenodeoxycholic acids remained unchanged whereas that of lithocholic acid increased slightly. A total of 64.6% of the orally administered TUDCA and 55.1% of the UDCA was absorbed (not significant). After TUDCA administration, biliary UDCA was preferentially (95.4%) taurine-conjugated whereas after UDCA administration biliary UDCA was mainly (79.8%) glycine-conjugated.

CONCLUSIONS

After oral administration of TUDCA and UDCA, no significant differences in their absorption and in biliary bile acid secretion exist. Whether biliary enrichment with taurine conjugates of UDCA instead of glycine conjugates offers advantages in the treatment of cholestatic liver disease is unclear at present.

Autoimmune hepatitis in children

AIH, ASC, and de novo AIH after liver transplantation are childhood liver diseases of an autoimmune nature. The mode of presentation of AIH in childhood is variable, and the disease should be suspected and excluded in all children presenting with symptoms and signs of prolonged or severe acute liver disease. Although corticosteroids are effective in all types of childhood AIH, patients with LKM1 have a higher frequency of acute hepatic failure and relapse after corticosteroid withdrawal than do patients with ANA/SMA. ASC occurs commonly in the absence of inflammatory bowel disease, requires cholangiography for diagnosis, and improves during corticosteroid therapy. The development of AIH de novo in children who undergo liver transplantation for nonautoimmune liver disease may reflect interference with the maturation of T cells by immunosuppressive drugs.

Taurolithocholic acid-3 sulfate induces CD95 trafficking and apoptosis in a c-Jun N-terminal kinase-dependent manner

BACKGROUND & AIMS

Prevention of bile acid-induced apoptosis is of therapeutic interest and requires the understanding of underlying mechanisms.

METHODS

The effect of tauroursodeoxycholate (TUDC) on taurolithocholic acid-3 sulfate (TLCS)-induced apoptosis was studied in cultured rat hepatocytes.

RESULTS

TLCS induced activation of caspases 8, 9, and 3 and hepatocyte apoptosis. These effects were abolished by TUDC in a PI 3-kinase-/protein kinase B (PKB)-, p38(MAPK)-, and extracellular signal-regulated kinase-2 (Erk-2)-independent manner. These protein kinases were activated by both TLCS and TUDC, however, with different kinetics. TLCS, but not TUDC, led to a sustained activation of c-Jun N-terminal kinase (JNK) and CD95 trafficking to the plasma membrane; both TLCS effects were prevented by TUDC. Inhibition of JNK1 or protein kinase C prevented TLCS-induced CD95 membrane trafficking and blunted the apoptotic response. The apoptotic potency of other bile acids paralleled their ability to induce sustained JNK activation.

CONCLUSIONS

Protection by TUDC against TLCS-induced apoptosis starts upstream of caspase 8 activation and is independent of a PI 3-kinase-dependent survival pathway. JNK activation may be important for bile acid-induced apoptosis by triggering ligand-independent CD95 surface trafficking and activation of apoptosis.

Management of primary sclerosing cholangitis

Guidelines for clinical practice are intended to indicate preferred approaches to medical problems as established by scientifically valid research. Double blind, placebo-controlled studies are preferable, but reports and expert review articles are also utilized in a thorough review of the literature conducted through the National Library of Medicine's MEDLINE. When only data that will not withstand objective scrutiny are available, a recommendation is identified as a consensus of experts. Guidelines are applicable to all physicians who address the subject, without regard to specialty training or interests, and are intended to indicate the preferable but not necessarily the only acceptable approach to a specific problem. Guidelines are intended to be flexible and must be distinguished from standards of care that are inflexible and rarely violated. Given the wide range of specifics in any health care problem, the physician must always choose the course best suited to the individual patient and the variables in existence at the moment of decision. Guidelines are developed under the auspices of the American College of Gastroenterology and its Practice Parameters Committee and approved by the Board of Trustees. Each has been intensely reviewed and revised by the Committee, other experts in the field, physicians who will use them, and specialists in the science of decision of analysis. The recommendations of each guideline are therefore considered valid at the time of their production based on the data available. New developments in medical research and practice pertinent to each guideline will be reviewed at an established time and indicated at publication to assure continued validity.

Development of dominant bile duct stenoses in patients with primary sclerosing cholangitis treated with ursodeoxycholic acid: outcome after endoscopic treatment

BACKGROUND/AIMS

Primary sclerosing cholangitis is characterized by progressive fibrotic inflammation and obliteration of intra- and/or extrahepatic bile ducts.

METHODS

In a prospective study of 106 patients treated for up to 13 years with ursodeoxycholic acid, the development of major bile duct stenoses and the efficacy of endoscopic measures have been evaluated.

RESULTS

Of 106 patients ten had major duct stenoses at entry, and during a median follow-up period of 5.0 years another 43 developed a dominant stenosis. Fifty-two patients with dominant stenoses were treated endoscopically by repeated balloon dilatations and five patients were temporarily stented. Complications of endoscopic procedures were pancreatitis (5.2%), bacterial cholangitis (3.3%) and bile duct perforation (0.5%). Five years after the first dilatation of a dominant stenosis the Kaplan-Meier survival rates free of liver transplantation were 100% in stage 2, 72% in stage 3 and 50% in stage 4 disease. The actuarial survival free of liver transplantation of the whole group at 3, 5 and 7 years were 0.987, 0.935 and 0.891 and the corresponding survival rates predicted with the Mayo multicenter survival model were 0.860, 0.775 and 0.737 (P<0.001).

CONCLUSIONS

In advanced disease, occlusion of major bile ducts with time occurs in the majority of patients. Endoscopic opening of dominant stenoses is effective and appears to be a valuable addition to the medical treatment of such patients.

Primary Sclerosing Cholangitis

There is no proven medical therapy for primary sclerosing cholangitis. The goal of management should be treatment of symptoms and complications of cholestasis, as well as attempts at treating the underlying disease process. In addition, efforts should be made to recognize and treat or prevent the known complications of primary sclerosing cholangitis, such as fat-soluble vitamin deficiency, osteopenia, dominant biliary strictures, and cholangiocarcinoma. Although some medical therapy has been shown to improve serum liver test or histology results, there has been no effect on survival or time to liver transplantation. However, preliminary data on high-dosage ursodeoxycholic acid have been encouraging. Liver transplantation remains the only effective treatment and is recommended for patients with end-stage liver disease and symptomatic portal hypertension, liver failure, and recurrent or intractable bacterial cholangitis.

A preliminary trial of high-dose ursodeoxycholic acid in primary sclerosing cholangitis

BACKGROUND & AIMS

Ursodeoxycholic acid (UDCA) is used for the treatment of cholestatic liver diseases including primary biliary cirrhosis (PBC) for which it has a positive effect on laboratory values, may delay the development of liver failure and prolong the transplant-free disease period. Standard doses of UDCA (8-15 mg/kg daily) have been shown to be ineffective in the treatment of primary sclerosing cholangitis (PSC). We report on the findings (clinical, biochemical, histological, and cholangiographic) and side effects of a 2-year double-blind placebo-controlled preliminary study of high-dose UDCA in PSC patients.

METHODS

Twenty-six patients with PSC were randomized to high-dose (20 mg/kg daily) UDCA or placebo. Cholangiography and liver biopsy were performed at entry and after 2 years. Symptoms, clinical signs, and liver biochemical tests were recorded at 3 monthly intervals.

RESULTS

High-dose UDCA did not influence symptoms, but there was a significant improvement in liver biochemistry (serum alkaline phosphatase, P = 0.03; gamma-glutamyl transferase, P = 0.01) and a significant reduction in progression in cholangiographic appearances (P = 0.015) and liver fibrosis as assessed by disease staging (P = 0.05). In the treatment group, a significant increase in total bile acids and saturation with UDCA >70% confirmed patient compliance. No significant side effects were reported.

CONCLUSIONS

High-dose UDCA may be of clinical benefit in PSC, but trials with a larger number of participants and of longer duration are required to establish whether the effect of high-dose UDCA on liver biochemistry, histology, and cholangiography in patients with PSC is translated into improved long-term survival.

Sclerosing cholangitis in the paediatric patient

Sclerosing cholangitis in childhood is a heterogeneous condition, which has different aetiologies. Sclerosing cholangitis may be inherited and diagnosed in the neonatal period (neonatal sclerosing cholangitis); it may present later with features of autoimmunity (autoimmune sclerosing cholangitis); or it may be associated with a variety of disorders, including Langerhans cell histiocytosis, immunodeficiency, psoriasis, cystic fibrosis, reticulum cell sarcoma and sickle cell anaemia. In contrast to the experience in adult patients, sclerosing cholangitis occurring as an individual disease (primary sclerosing cholangitis) is rare. The initiating events and possible pathogenic mechanisms differ in the various forms of sclerosing cholangitis and are still obscure. Treatment and prognosis depend on the type of sclerosing cholangitis present.

Tauroursodesoxycholate-induced choleresis involves p38(MAPK) activation and translocation of the bile salt export pump in rats

BACKGROUND & AIMS

Canalicular secretion of bile acids is stimulated by tauroursodesoxycholate (TUDC). This study investigates the underlying mechanisms.

METHODS

TUDC effects on mitogen-activated protein (MAP) kinases, taurocholate (TC) excretion, proteolysis, and the localization of the bile salt export pump (Bsep) were studied in rat hepatocytes and perfused liver.

RESULTS

TUDC induced a transient and concentration-dependent activation of p38(MAPK) and of extracellular signal-regulated kinase 2 (Erk-2), but not of c-Jun-N-terminal kinase (JNK). In perfused liver, TUDC concentrations of 20 micromol/L was sufficient to elicit the MAP kinase responses and TC choleresis. SB 202190, a specific inhibitor of p38(MAPK), had no effect on TUDC- induced Erk activation but abolished the stimulatory effect of TUDC on TC excretion in perfused liver, indicating the requirement of p38(MAPK) in addition to the reported Erk dependence for the choleretic response. TUDC-induced stimulation of TC excretion was accompanied by a p38(MAPK)-dependent insertion of subcanalicular immunoreactive Bsep into the canalicular membrane. In addition TUDC induced a p38(MAPK)-sensitive inhibition of proteolysis.

CONCLUSIONS

TUDC-induced stimulation of canalicular TC excretion involves a MAP kinase-dependent translocation of subcanalicular Bsep to the canalicular membrane. Dual activation of Erks and p38(MAPK) is required for the choleretic effect of both TUDC and hypo-osmotic cell swelling.

Medical and endoscopic treatment in primary sclerosing cholangitis

Primary sclerosing cholangitis is an important cause of chronic cholestatic liver disease. The aetiology is still unknown and an immunological basis is discussed. The disease results in diffuse narrowing and irregularities of intra- and extra-hepatic bile ducts that may lead to biliary cirrhosis. Progression of the disease is highly variable and fluctuating. An important issue is the risk for developing cholangiocarcinoma. For end-stage disease liver transplantation is the only therapeutic option. If strictures of the extra-hepatic bile ducts are demonstrable, endoscopic interventions are effective palliative treatment options. The use of immunosuppressive or anti-inflammatory drugs has been shown to have no influence on the course of primary sclerosing cholangitis.

Ursodeoxycholic acid 'mechanisms of action and clinical use in hepatobiliary disorders'

UDCA exerts its beneficial effect in liver diseases through a diverse, probably, complementary array of mechanisms. The clinical use and efficacy of UDCA in PBC have been evident. UDCA may also have a place in the management of PSC, ICP, cystic fibrosis, PFIC and GVHD involving the liver, although, more studies are needed to further determine its therapeutic potential in these diseases and in other hepatobiliary disorders such as liver allograft rejection, drug and TPN-induced cholestasis, NASH, and alcoholic liver disease.

The therapeutic effects of ursodeoxycholic acid as an anti-apoptotic agent

The dihydroxy bile acid, ursodeoxycholic acid (UDCA), has been in widespread clinical use in the Western world since the mid 1980s, when it was initially used for gallstone dissolution [1,2] and subsequently for the treatment of chronic cholestatic liver diseases [3,4]. Many clinical trials of UDCA in a variety of cholestatic disorders established biochemical and clinical improvements, and most importantly showed a significant prolongation of transplant-free survival after four years of treatment with UDCA in patients with primary biliary cirrhosis [5]. Despite its clinical efficacy, the precise mechanism(s) by which UDCA improves liver function during cholestasis is still a matter of debate [6]. It was initially considered that the choleretic effect of UDCA, coupled with its ability to cause a marked shift in the composition of the bile acid pool towards hydrophilicity, accounted for its mechanism of action. In recent years, however, it has become evident that UDCA and its conjugated derivatives are capable of exerting direct effects at the cellular, subcellular, and molecular levels by stabilising cell membranes, affecting signal transduction pathways, and regulating immune responses. In addition, we have shown that UDCA plays a unique role in modulating the apoptotic threshold in both hepatic and non-hepatic cells [7-10]. The purpose of this article is to examine the mechanism(s) by which UDCA prevents apoptotic cell death associated with cholestasis. In addition, we will also review a potentially novel and, heretofore, unrecognised role of UDCA as a therapeutic agent in the treatment of non-liver diseases associated with increased levels of apoptosis as a pathogenesis of the disorder.

High-dose ursodeoxycholic acid as a therapy for patients with primary sclerosing cholangitis

OBJECTIVES

To assess the tolerability and efficacy of high-dose (25-30 mg/kg per day) ursodeoxycholic acid (UDCA) in patients with primary sclerosing cholangitis (PSC).

METHODS

Thirty patients with PSC were enrolled in this pilot study and treated for 1 yr. Changes in the Mayo risk score at 1 yr of treatment and projected survival at 4 yr were compared with that observed in patients randomized to placebo (n = 52) or UDCA (n = 53) at a dose of 13-15 mg/kg per day.

RESULTS

A marked improvement in serum alkaline phosphatase activity (1265+/-172 vs 693+/-110 U/L, p < 0.001), AST (161+/-037 vs 77+/-13 U/L, p = 0.001), albumin (4.0+/-0.1 vs 4.2+/-0.1 g/dl, p = 0.03), and total bilirubin (1.6+/-0.3 vs 1.3+/-0.2 mg/dl, p = 0.1) occurred at 1 yr of therapy with high-dose UDCA. Changes in the Mayo risk score after 1 yr of treatment were significantly different among the three groups (p < 0.001), and these changes would be translated into a significantly different expected survival at 4 yr (p = 0.05). This expected survival at 4 yr was significantly different between placebo and the dose of 25-30 mg/kg per day (p = 0.04), but not between placebo and the dose of 13-15 mg/kg per day (p = 0.4). High-dose UDCA was well tolerated.

CONCLUSIONS

UDCA at a dose of 25-30 mg/kg per day may be of benefit for patients with PSC, and this regimen deserves further evaluation in a long-term, randomized, placebo-controlled trial.

No beneficial effects of transdermal nicotine in patients with primary sclerosing cholangitis: results of a randomized double-blind placebo-controlled cross-over study

BACKGROUND/AIMS

Smoking is associated with a decreased risk of primary sclerosing cholangitis. We aimed to explore the therapeutic efficacy of and tolerance for transdermal nicotine treatment in this disease.

METHODS

Twelve patients (11 males; 37 +/- 6 years; six with ulcerative colitis) who did not achieve complete biochemical remission on ursodeoxycholic acid (14 mg/ kg/day) were treated in a randomized cross-over trial with transdermal nicotine (15 mg/day) or a placebo, each for 8 weeks (4-week washout period between treatments).

RESULTS

One patient developed de novo ulcerative colitis and two did not complete the entire protocol because of intercurrent bacterial cholangitis. Baseline values [mean (range)] were: bilirubin, 1.3 (0.5-2.6); alkaline phosphatase (APh), 2.5 (1.4-4.7); gamma-glutamyl transpeptidase (gammaGT), 7.7 (0.7-38); aspartate aminotransferase (AST), 1.9 (0.5-3.2); alanine aminotransferase (ALT), 2.4 (0.4-7.3); and bile salts, 10.9 (2.1 -39) times the upper limit of normal. No significant effect on pruritus or fatigue was noted during either period, but a small increase in bodyweight was observed during placebo treatment. No significant differences were observed between the two treatment modalities after 8 weeks in bilirubin (nicotine versus placebo, +13% versus -6% change from baseline), APh (-3% versus -17%), gammaGT (-11% versus -13%), AST (+2% versus -10%), ALT (-1% versus -11%) or bile salts (+36% versus -3%).

CONCLUSION

Transdermal nicotine does not seem to have a clear short-term beneficial effect in primary sclerosing cholangitis treated with ursodeoxycholic acid.

Phosphoinositide 3-kinase-dependent Ras activation by tauroursodesoxycholate in rat liver

Ursodesoxycholic acid, widely used for the treatment of cholestatic liver disease, causes choleretic, anti-apoptotic and immunomodulatory effects. Here the effects on choleresis of its taurine conjugate tauroursodesoxycholate (TUDC), which is present in the enterohepatic circulation, were correlated with the activation of important elements of intracellular signal transduction in cultured rat hepatocytes and perfused rat liver. TUDC induced a time- and concentration-dependent activation of the small GTP-binding protein Ras and of phosphoinositide 3-kinase (PI 3-kinase) in cultured hepatocytes. Ras activation was dependent on PI 3-kinase activity, without the involvement of protein kinase C- and genistein-sensitive tyrosine kinases. Ras activation by TUDC was followed by an activation of the mitogen-activated protein kinases extracellular-signal-regulated kinase-1 (Erk-1) and Erk-2. In perfused rat liver, PI 3-kinase inhibitors largely abolished the stimulatory effect of TUDC on taurocholate excretion, suggesting an important role for a PI 3-kinase/Ras/Erk pathway in the choleretic effect of TUDC.