Ursodeoxycholic acid cytoprotection: dancing with death receptors and survival pathways

Ursodeoxycholic acid shows antineoplastic effects in bile duct cancer cells via apoptosis induction; p53 activation; and EGFR-ERK, COX-2, and PI3K-AKT pathway inhibition

Unlike in normal cells, ursodeoxycholic acid (UDCA) causes apoptosis rather than protection in cancer cells. Aim of this study was to demonstrate whether UDCA actually inhibits proliferation and induces apoptosis in bile duct cancer cells; the effect of UDCA on the expression of COX-2, PI3K/AKT, ERK, and EGFR; how UDCA affects cancer cell invasiveness and metastasis, since these effects are not established in bile duct cancer cells. SNU-245 cells (human extrahepatic bile duct cancer cells) were cultured. MTT assays were performed to evaluate the effect of UDCA on the cell proliferation. A cell death detection enzyme-linked immunosorbent assay and a caspase-3 activity assay were used to determine apoptosis. Western blot analysis measured expression levels of various proteins. The invasiveness of the cancer cells was evaluated by invasion assay. In cultured bile duct cancer cells, UDCA suppressed cell proliferation in bile duct cancer cells by inducing apoptosis and p53 activation, blocking deoxycholic acid (DCA)-induced activated EGFR-ERK signaling and COX-2, inhibiting DCA-induced activated PI3K-AKT signaling, and suppressing the invasiveness of bile duct cancer cells. In addition, a MEK inhibitor impaired UDCA-induced apoptosis in bile duct cancer cells. UDCA has antineoplastic and apoptotic effects in bile duct cancer cells. Thus, UDCA could be a chemopreventive agent in patients with a high risk of cancer, and/or a therapeutic option that enhances other chemotherapeutics.

Inflammation: Cause or consequence of chronic cholestatic liver injury

Cholestasis is a result of obstruction of the biliary tracts. It is a common cause of liver pathology after exposure to toxic xenobiotics and during numerous other liver diseases. Accumulation of bile acids in the liver is thought to be a major driver of liver injury during cholestasis and can lead to eventual liver fibrosis and cirrhosis. As such, current therapy in the field of chronic liver diseases with prominent cholestasis relies heavily on increasing choleresis to limit accumulation of bile acids. Many of these same diseases also present with autoimmunity before the onset of cholestasis though, indicating the inflammation may be an initiating component of the pathology. Moreover, cytotoxic inflammatory mediators accumulate during cholestasis and can propagate liver injury. Anti-inflammatory biologics and small molecules have largely failed clinical trials in these diseases though and as such, targeting inflammation as a means to address cholestatic liver injury remains debatable. The purpose of this review is to understand the different roles that inflammation can play during cholestatic liver injury and attempt to define how new therapeutic targets that limit or control inflammation may be beneficial for patients with chronic cholestatic liver disease.

Ursodeoxycholic acid induces apoptosis of hepatocellular carcinoma cells in vitro

OBJECTIVE

Ursodeoxycholic acid (UDCA) is widely used to treat chronic liver diseases, and its cytoprotective effect on normal hepatocytes has been shown. This study aimed to investigate the apoptotic effects of UDCA on hepatocellular carcinoma (HCC) cells and the underlying molecular events in vitro.

METHODS

HCC cells were treated by UDCA at different doses and periods of time to assess cell morphology, viability, apoptosis and gene expression using methyl thiazolyl tetrazolium (MTT), Annexin V/propidium iodide (PI) stain, transferase dUTP nick end labeling (TUNEL), enzyme-linked immunosorbent assay (ELISA), immunocytochemistry and quantitative reverse transcription polymerase chain reaction, respectively.

RESULTS

UDCA treatment reduced cell viability but induced HCC cell apoptosis in dose-dependent and time-dependent manners. UDCA arrested HepG2 cells at phase S of the cell cycle. At the gene levels, UDCA downregulated Bcl-2 and second mitochondria-derived activator of caspase (Smac) protein expressions, but upregulated Bax and Livin proteins in HCC cells. At the highest concentration, UDCA inhibited Livin mRNA expression but increased Smac and caspase-3 mRNA expressions as well as the activity of caspase-3 in HCC cells.

CONCLUSIONS

The induction of HCC cell apoptosis by UDCA was dose-dependent and time-dependent and was mediated by the regulation of Bax to Bcl-2 ratio, the expressions of Smac and Livin, and caspase-3 expression and activity.

Clinical application of transcriptional activators of bile salt transporters

Hepatobiliary bile salt (BS) transporters are critical determinants of BS homeostasis controlling intracellular concentrations of BSs and their enterohepatic circulation. Genetic or acquired dysfunction of specific transport systems causes intrahepatic and systemic retention of potentially cytotoxic BSs, which, in high concentrations, may disturb integrity of cell membranes and subcellular organelles resulting in cell death, inflammation and fibrosis. Transcriptional regulation of canalicular BS efflux through bile salt export pump (BSEP), basolateral elimination through organic solute transporters alpha and beta (OSTα/OSTβ) as well as inhibition of hepatocellular BS uptake through basolateral Na(+)-taurocholate cotransporting polypeptide (NTCP) represent critical steps in protection from hepatocellular BS overload and can be targeted therapeutically. In this article, we review the potential clinical implications of the major BS transporters BSEP, OSTα/OSTβ and NTCP in the pathogenesis of hereditary and acquired cholestatic syndromes, provide an overview on transcriptional control of these transporters by the key regulatory nuclear receptors and discuss the potential therapeutic role of novel transcriptional activators of BS transporters in cholestasis.

PSC, AIH and overlap syndrome in inflammatory bowel disease

Primary sclerosing cholangitis (PSC) is a progressive, cholestatic disorder characterised by chronic inflammation and stricture formation of the biliary tree. Symptoms include pruritus, fatigue and in advanced cases ascending cholangitis, cirrhosis and end-stage hepatic failure. Patients are at an increased risk of malignancy arising from the bile ducts, gallbladder, liver and colon. The majority (>80%) of Northern European patients with PSC also have inflammatory bowel disease (IBD), usually ulcerative colitis (UC). IBD commonly presents before the onset of PSC, although the opposite can occur and the onset of both conditions can be separated by many years. The colitis associated with PSC is characteristically mild although frequently involves the whole colon. Despite the majority of patients having relatively inactive colonic disease, paradoxically the risk of colorectal malignancy is substantially increased. Patients may also develop dominant, stenotic lesions of the biliary tree which may be difficult to differentiate from cholangiocarcinoma and the coexistence of IBD may influence the development of this complication. Ursodeoxycholic acid may offer a chemoprotective effect against colorectal malignancy and improve liver biochemical indices. Evidence of any beneficial effect on histological progression of hepatobiliary disease is less clear. High doses (∼25-30 mg/kg/d) may be harmful and should be avoided. Autoimmune hepatitis (AIH) is less common in patients with IBD than PSC, however, an association has been observed. A small subgroup may have an overlap syndrome between AIH and PSC and management should be individualised dependant on liver histology, serum immunoglobulin levels, autoantibodies, degree of biochemical cholestasis and cholangiography.

Ursodeoxycholic acid in cholestasis: linking action mechanisms to therapeutic applications

UDCA (ursodeoxycholic acid) is the therapeutic agent most widely used for the treatment of cholestatic hepatopathies. Its use has expanded to other kinds of hepatic diseases, and even to extrahepatic ones. Such versatility is the result of its multiple mechanisms of action. UDCA stabilizes plasma membranes against cytolysis by tensioactive bile acids accumulated in cholestasis. UDCA also halts apoptosis by preventing the formation of mitochondrial pores, membrane recruitment of death receptors and endoplasmic-reticulum stress. In addition, UDCA induces changes in the expression of metabolizing enzymes and transporters that reduce bile acid cytotoxicity and improve renal excretion. Its capability to positively modulate ductular bile flow helps to preserve the integrity of bile ducts. UDCA also prevents the endocytic internalization of canalicular transporters, a common feature in cholestasis. Finally, UDCA has immunomodulatory properties that limit the exacerbated immunological response occurring in autoimmune cholestatic diseases by counteracting the overexpression of MHC antigens and perhaps by limiting the production of cytokines by immunocompetent cells. Owing to this multi-functionality, it is difficult to envisage a substitute for UDCA that combines as many hepatoprotective effects with such efficacy. We predict a long-lasting use of UDCA as the therapeutic agent of choice in cholestasis.

Bile acids for primary sclerosing cholangitis

BACKGROUND

Primary sclerosing cholangitis is a progressive chronic cholestatic liver disease that usually leads to the development of cirrhosis. Studies evaluating bile acids in the treatment of primary sclerosing cholangitis have shown a potential benefit of their use. However, no influence on patients survival and disease outcome has yet been proven.

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 Controlled Trials Register, The Cochrane Library, MEDLINE, EMBASE and Science Citation Index Expanded generally from inception through to October 2010.

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

Two authors extracted data independently. We evaluated the risk of bias of the trials using prespecified domains. We performed the meta-analysis according to the intention-to-treat principle. We presented outcomes as relative risks (RR) or mean differences (MD), both with 95% confidence intervals (CI).

MAIN RESULTS

Eight trials evaluated ursodeoxycholic acid versus placebo or no intervention (592 patients). The eight randomised clinical trials have a high risk of bias. Patients were treated for three months to six years (median three years). The dosage of ursodeoxycholic acid used in the trials ranged from low (10 mg/kg body weight/day) to high (28 to 30 mg/kg body weight/day). Ursodeoxycholic acid did not significantly reduce the risk of death (RR 1.00; 95% CI 0.46 to 2.20); treatment failure including liver transplantation, varices, ascites, and encephalopathy (RR 1.22; 95% CI 0.91 to 1.64); liver histological deterioration (RR 0.89; 95% CI 0.45 to 1.74); or liver cholangiographic deterioration (RR 0.60; 95% CI 0.23 to 1.57). Ursodeoxycholic acid significantly improved serum bilirubin (MD -14.6 µmol/litre; 95% CI -18.7 to -10.6), alkaline phosphatases (MD -506 IU/litre; 95% CI -583 to -430), aspartate aminotransferase (MD -46 IU/litre; 95% CI -77 to -16), and gamma-glutamyltranspeptidase (MD -260 IU/litre; 95% CI -315 to -205), but not albumin (MD -0.20 g/litre; 95% CI -1.91 to 1.50). Ursodeoxycholic acid was safe and well tolerated by patients with primary sclerosing cholangitis.

AUTHORS' CONCLUSIONS

We did not find enough evidence to support or refute the use of bile acids in the treatment of primary sclerosing cholangitis. However, bile acids seem to lead to a significant improvement in liver biochemistry. Therefore, more randomised trials are needed before any of the bile acids can be recommended for this indication.

Bile acids: regulation of apoptosis by ursodeoxycholic acid

Bile acids are a group of molecular species of acidic steroids with peculiar physical-chemical and biological characteristics. At high concentrations they become toxic to mammalian cells, and their presence is pertinent in the pathogenesis of several liver diseases and colon cancer. Bile acid cytoxicity has been related to membrane damage, but also to nondetergent effects, such as oxidative stress and apoptosis. Strikingly, hydrophilic ursodeoxycholic acid (UDCA), and its taurine-conjugated form (TUDCA), show profound cytoprotective properties. Indeed, these molecules have been described as potent inhibitors of classic pathways of apoptosis, although their precise mode of action remains to be clarified. UDCA, originally used for cholesterol gallstone dissolution, is currently considered the first choice therapy for several forms of cholestatic syndromes. However, the beneficial effects of both UDCA and TUDCA have been tested in other experimental pathological conditions with deregulated levels of apoptosis, including neurological disorders, such as Alzheimer's, Parkinson's, and Huntington's diseases. Here, we review the role of bile acids in modulating the apoptosis process, emphasizing the anti-apoptotic effects of UDCA and TUDCA, as well as their potential use as novel and alternate therapeutic agents for the treatment of apoptosis-related diseases.

Tauroursodeoxycholic acid reduces bile acid-induced apoptosis by modulation of AP-1

Ursodeoxycholic acid (UDCA) is used in the therapy of cholestatic liver diseases. Apoptosis induced by toxic bile acids plays an important role in the pathogenesis of liver injury during cholestasis and appears to be mediated by the human transcription factor AP-1. We aimed to study if TUDCA can decrease taurolitholic acid (TLCA)-induced apoptosis by modulating AP-1. TLCA (20 microM) upregulated AP-1 proteins cFos (26-fold) and JunB (11-fold) as determined by quantitative real-time PCR in HepG2-Ntcp hepatoma cells. AP-1 transcriptional activity increased by 300% after exposure to TLCA. cFos and JunB expression as well as AP-1 transcriptional activity were unaffected by TUDCA (75 microM). However, TUDCA significantly decreased TLCA-induced upregulation of cFos and JunB. Furthermore, TUDCA inhibited TLCA-induced AP-1 transcriptional activity and reduced TLCA-induced apoptosis. These data suggest that reversal of bile acid-induced AP-1 activation may be relevant for the antiapoptotic effect of TUDCA in liver cells.

Bile acids for viral hepatitis

BACKGROUND

Trials have assessed bile acids for patients with viral hepatitis, but no consensus has been reached regarding their usefulness.

OBJECTIVES

To assess the beneficial and harmful effects of bile acids for viral hepatitis.

SEARCH STRATEGY

Searches were performed in The Cochrane Hepato-Biliary Group Controlled Trials Register (July 2007), The Cochrane Library (Issue 1, 2007), MEDLINE (July 2007), EMBASE (July 2007), Science Citation Index Expanded (July 2007), and Chinese Biomedical Database (July 2007).

SELECTION CRITERIA

Randomised clinical trials comparing any dose or duration of bile acids versus placebo or no intervention for viral hepatitis were included, irrespective of language, publication status, or blinding. Co-interventions were allowed in the included randomised clinical trials.

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

We identified 29 randomised trials of bile acids for hepatitis B or C; none were of high methodological quality. We were unable to extract data from two trials. In one trial, ursodeoxycholic acid (UDCA) versus placebo for acute hepatitis B significantly reduced the risk of hepatitis B surface antigen positivity at the end of treatment and serum HBV DNA level at the end of follow-up. In another trial, UDCA versus no intervention for chronic hepatitis B significantly reduced the risk of having abnormal serum transaminase activities at the end of treatment. Twenty-five trials compared bile acids (21 trials UDCA; four trials tauro-UDCA) versus placebo or no intervention with or without co-interventions for chronic hepatitis C. Bile acids did not significantly reduce the risk of having detectable serum HCV RNA (RR 0.99, 95% CI 0.91 to 1.07), cirrhosis, or portal and periportal inflammation score at the end of treatment. Bile acids significantly decreased the risk of having abnormal serum alanine aminotransferase activity at the end of treatment (RR 0.82, 95% CI 0.76 to 0.90) and follow-up (RR 0.91, 95% CI 0.85 to 0.98). Bile acids significantly increased the Knodell score (WMD 0.20, 95% CI 0.08 to 0.31) at the end of treatment. No severe adverse events were reported. We did not identify trials including patients with hepatitis A, acute hepatitis C, hepatitis D, or hepatitis E.

AUTHORS' CONCLUSIONS

Bile acids lead to a significant improvement in serum transaminase activities in hepatitis B and C but have no effects on the clearance of virus. There is insufficient evidence either to support or to refute effects on long-term outcomes including hepatocellular carcinoma, hepatic decompensation, and liver related mortality. Randomised trials with high methodological quality are required before clinical use is considered.

Ursodeoxycholic acid treatment of vanishing bile duct syndromes

Vanishing bile duct syndromes (VBDS) are characterized by progressive loss of small intrahepatic ducts caused by a variety of different diseases leading to chronic cholestasis, cirrhosis, and premature death from liver failure. The majority of adult patients with VBDS suffer from primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). Ursodeoxycholic acid (UDCA), a hydrophilic dihydroxy bile acid, is the only drug currently approved for the treatment of patients with PBC, and anticholestatic effects have been reported for several other cholestatic syndromes. Several potential mechanisms of action of UDCA have been proposed including stimulation of hepatobiliary secretion, inhibition of apoptosis and protection of cholangiocytes against toxic effects of hydrophobic bile acids.

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.

Tauroursodeoxycholic acid prevents amyloid-beta peptide-induced neuronal death via a phosphatidylinositol 3-kinase-dependent signaling pathway

Tauroursodeoxycholic acid (TUDCA), an endogenous bile acid, modulates cell death by interrupting classic pathways of apoptosis. Amyloid-beta (Abeta) peptide has been implicated in the pathogenesis of Alzheimer's disease, where a significant loss of neuronal cells is thought to occur by apoptosis. In this study, we explored the cell death pathway and signaling mechanisms involved in Abeta-induced toxicity and further investigated the anti-apoptotic effect(s) of TUDCA. Our data show significant induction of apoptosis in isolated cortical neurons incubated with Abeta peptide. Apoptosis was associated with translocation of pro-apoptotic Bax to the mitochondria, followed by cytochrome c release, caspase activation, and DNA and nuclear fragmentation. In addition, there was almost immediate but weak activation of the serine/threonine protein kinase Akt. Inhibition of the phosphatidylinositide 3 prime-OH kinase (PI3K) pathway with wortmannin did not markedly affect Abeta-induced cell death, suggesting that this signaling pathway is not crucial for Abeta-mediated toxicity. Notably, co-incubation with TUDCA significantly modulated each of the Abeta-induced apoptotic events. Moreover, wortmannin decreased TUDCA protection against Abeta-induced apoptosis, reduced Akt phosphorylation, and increased Bax translocation to mitochondria. Together, these findings indicate that Abeta-induced apoptosis of cortical neurons proceeds through a Bax mitochondrial pathway. Further, the PI3K signaling cascade plays a role in regulating the anti-apoptotic effects of TUDCA.

Ursodeoxycholic Acid Can Suppress Deoxycholic Acid-Induced Apoptosis by Stimulating Akt/PKB-Dependent Survival Signaling

The nontoxic bile acid ursodeoxycholic acid (UDCA) is reported to be an anti-apoptotic agent with efficacy against a variety of death stimuli including the cytotoxic bile acid deoxycholic acid (DCA). To gain insight into this anti-apoptotic property, we tested UDCA for its ability to protect the colon carcinoma-derived cell line HCT116 against DCA-induced apoptosis. We found that UDCA could suppress DCA-induced apoptosis in a time- and dose-dependent manner and that this effect correlated with Akt phosphorylation. Importantly, UDCA lost its ability to protect cells from DCA-induced cell death when Akt activity was suppressed genetically using a dominant negative Akt mutant or when PI3K activity was inhibited pharmacologically. These results suggest that UDCA can protect HCT116 cells against DCA-induced apoptosis by stimulating Akt-dependent survival signaling.

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.

Cholestatic syndromes

Further insights into the cellular and molecular mechanisms underlying hepatobiliary transport function and its regulation now permit a better understanding of the pathogenesis and treatment options of cholestatic liver diseases. Identification of the molecular basis of hereditary cholestatic syndromes will result in an improved diagnosis and management of these conditions. New insights into the pathogenesis of extrahepatic manifestations of cholestasis (eg, pruritus) have facilitated new treatment strategies. Important new studies have been published about the pathogenesis, clinical features, diagnosis, and treatment of primary biliary cirrhosis, primary sclerosing cholangitis, cholestasis of pregnancy, total parenteral nutrition-induced cholestasis, drug-induced cholestasis, and viral cholestatic syndromes.

The effect of ursodeoxycholic acid on the survivin in thapsigargin-induced apoptosis

Endoplasmic reticulum (ER) was recently suggested as a third subcellular compartment in apoptotic execution. Survivin is a member of inhibitors of apoptosis and ursodeoxycholic acid (UDCA) prevents apoptosis from various apoptotic stimuli. To assess the activity of survivin and the effect of UDCA on the survivin in ER stress-mediated apoptosis, we treated hepatoma cell lines with thapsigargin (TG). TG-induced apoptosis was assessed by morphological changes, DNA fragmentation, cleavages of poly(ADP-ribose)polymerase (PARP), and activation of calpain and caspase-12. The level of survivin was decreased after TG treatment in hepatoma cell lines indicating that survivin play an important role in ER stress-mediated apoptosis. UDCA prevented decrease in survivin levels and inhibited TG-induced apoptosis and caspase-12 activation suggesting an anti-apoptotic effect of UDCA.

Bile acids for viral hepatitis

BACKGROUND

The viral hepatitides are common causes of liver diseases globally. Trials have assessed bile acids for patients with viral hepatitis, but no consensus was reached regarding their usefulness.

OBJECTIVES

To assess the beneficial and harmful effects of bile acids for viral hepatitis.

SEARCH STRATEGY

Searches were performed of the trial registers of The Cochrane Hepato-Biliary Group (September 2002), The Cochrane Library (Issue 2, 2002), MEDLINE (September 2002), EMBASE (September 2002), and The Chinese Biomedical Database (April 2001).

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

We identified 27 randomised trials of bile acids for hepatitis B or C; none were of high methodological quality. In one trial, ursodeoxycholic acid (UDCA) versus placebo for acute hepatitis B significantly reduced the risk of hepatitis B surface antigen positivity at the end of treatment and serum HBV DNA level at the end of follow-up. In another trial, UDCA versus no intervention for chronic hepatitis B significantly reduced the risk of having abnormal serum transaminase activities at the end of treatment. Twenty-five trials compared bile acids (21 trials UDCA; four trials tauro-UDCA) versus placebo or no intervention with or without co-interventions for chronic hepatitis C. Bile acids did not significantly reduce the risk of having detectable serum HCV RNA (RR 0.99, 95% CI 0.91 to 1.07), cirrhosis, or portal and periportal inflammation score at the end of treatment. Bile acids significantly decreased the risk of having abnormal serum alanine aminotransferase activity at the end of treatment (RR 0.82, 95% CI 0.76 to 0.90) and follow-up (RR 0.91, 95% CI 0.85 to 0.98). Bile acids significantly increased the Knodell score (WMD 0.20, 95% CI 0.08 to 0.31) at the end of treatment. No severe adverse events were reported. We did not identify trials including patients with hepatitis A, acute C, D, or E.

REVIEWER'S CONCLUSIONS

Bile acids lead to a significant improvement in serum transaminase activities in hepatitis B and C. There is insufficient evidence either to support or to refute effects on viral markers, mortality, incidence of cirrhosis, or liver histology. Trials with high methodological quality are required.

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.