Effect of ursodeoxycholic acid in acute viral hepatitis

Synthesis of (125) I-lamivudine and (125) I-lamivudine-ursodeoxycholic acid codrug

The preparation of (125) I-lamivudine ((125) I-3TC) and (125) I-lamivudine-ursodeoxycholic acid codrug ((125) I-3TC-UDCA), suitable for comparative biodistribution studies, is described. The synthesis of the unlabeled precursor 3TC-UDCA proceeds in an 11.6% yield, and the radiolabelling yields for (125) I-3TC and (125) I-3TC-UDCA were 89 and 92%, respectively. The final products are radiochemically pure (greater than 98%).

Treatment of severe, nonfulminant acute hepatitis B with lamivudine vs placebo: a prospective randomized double-blinded multicentre trial

Acute hepatitis B virus (aHBV) infection can lead to fulminant liver failure, which likely is prevented by early lamivudine therapy. Even nonfulminant but severe acute hepatitis B can lead to significant morbidity and impaired quality of life. Therefore, lamivudine was evaluated in patients with severe aHBV in a placebo-controlled trial. Patients with severe aHBV infection (ALT >10× ULN, bilirubin >85 μm, prothrombin time >50%) were prospectively treated with lamivudine 100 mg/day or with placebo within 8 days after the diagnosis. The primary end point was time to bilirubin <34.2 μm. Secondary end points were time to clear HBsAg and HBV-DNA, development of anti-HBs and normalization of ALT. Eighteen cases were randomized to lamivudine, 17 to placebo. 94% of patients were hospitalized. No individual progressed to hepatic failure; all but one patient achieved the primary end point. Due to smaller than expected patient numbers, all study end points did not become statistically significant between treatment arms. Median time end points [in days] were bilirubin <34.2 μm (26.5 vs 32), ALT normalization (35 vs 48) and HBsAg clearance (48 vs 67) referring to earlier recovery under lamivudine, in contrast to loss of HBV-DNA (62 vs 54) and development of anti-HBs (119 vs 109). In all but two patients (one in every group), HBsAg clearance was reached in the study. Adverse events occurred more frequently during lamivudine therapy, but did not reach statistical significance. Lamivudine may ameliorate severe aHBV infection, but limited patient numbers prevented definite conclusions.

Recommendations for the management of acute hepatitis B: position paper of the Italian Society for the Study of Infectious and Tropical Diseases (SIMIT)

PURPOSE

To develop recommendations for the management of acute hepatitis B by the Italian Society for the Study of Infectious and Tropical Diseases.

METHODS

Development of the recommendations divided into three levels of evidence according to the GRADE system: A (high), B (medium) and C (low experts opinion), together with three recommendation levels: 1 (strong), 2 (medium), 3 (weak).

RESULTS

The treatment with antivirals is in selected cases the mainstay of management of severe acute hepatitis, and should be started as a matter of urgency in order to prevent death.

CONCLUSIONS

These recommendations are meant to provide the rationale and practical indications for the management of acute hepatitis B (AHB).

Viral entry of hepatitis B and D viruses and bile salts transportation share common molecular determinants on sodium taurocholate cotransporting polypeptide

The liver bile acids transporter sodium taurocholate cotransporting polypeptide (NTCP) is responsible for the majority of sodium-dependent bile salts uptake by hepatocytes. NTCP also functions as a cellular receptor for viral entry of hepatitis B virus (HBV) and hepatitis D virus (HDV) through a specific interaction between NTCP and the pre-S1 domain of HBV large envelope protein. However, it remains unknown if these two functions of NTCP are independent or if they interfere with each other. Here we show that binding of the pre-S1 domain to human NTCP blocks taurocholate uptake by the receptor; conversely, some bile acid substrates of NTCP inhibit HBV and HDV entry. Mutations of NTCP residues critical for bile salts binding severely impair viral infection by HDV and HBV; to a lesser extent, the residues important for sodium binding also inhibit viral infection. The mutation S267F, corresponding to a single nucleotide polymorphism (SNP) found in about 9% of the East Asian population, renders NTCP without either taurocholate transporting activity or the ability to support HBV or HDV infection in cell culture. These results demonstrate that molecular determinants critical for HBV and HDV entry overlap with that for bile salts uptake by NTCP, indicating that viral infection may interfere with the normal function of NTCP, and bile acids and their derivatives hold the potential for further development into antiviral drugs.

IMPORTANCE

Human hepatitis B virus (HBV) and its satellite virus, hepatitis D virus (HDV), are important human pathogens. Available therapeutics against HBV are limited, and there is no drug that is clinically available for HDV infection. A liver bile acids transporter (sodium taurocholate cotransporting polypeptide [NTCP]) critical for maintaining homeostasis of bile acids serves as a functional receptor for HBV and HDV. We report here that the NTCP-binding lipopeptide that originates from the first 47 amino acids of the pre-S1 domain of the HBV L protein blocks taurocholate transport. Some bile salts dose dependently inhibit HBV and HDV infection mediated by NTCP; molecular determinants of NTCP critical for HBV and HDV entry overlap with that for bile acids transport. This work advances our understanding of NTCP-mediated HBV and HDV infection in relation to NTCP's physiological function. Our results also suggest that bile acids or their derivatives hold potential for development into novel drugs against HBV and HDV infection.

Management of severe acute to fulminant hepatitis B: to treat or not to treat or when to treat?

Despite a decline in cases of acute hepatitis B and the low hepatitis B virus (HBV) chronicity rates in adults, still some patients progress to HBV-related fulminant liver failure. In this review, we discuss treatment options that may prevent the progression of severe acute hepatitis B to fulminant liver failure and death. In severe acute HBV with prolonged prothrombin time and increased bilirubin, interferon failed to be effective while antiviral treatment, particularly with lamivudine, appears to improve survival (mean survival almost 80%). Outcome without antiviral therapy has remained considerably poor, whereas there is no convincing evidence of amelioration of HBV-targeted immunity. Of note, most patients who died or required transplantation despite lamivudine therapy, were started on lamivudine at advanced stages compared with those survived. This suggests that prompt and timely antiviral therapy is crucial. Owing to the abovementioned results the design of randomized placebo-control trials in the setting of severe acute hepatitis B seems unethical. On the contrary, the design of multicentre double-blind randomized trials to compare the efficacy between lamivudine and entecavir or even tenofovir in acute severe HBV cases is ideally needed, but these studies appear to be very difficult to perform considering that these cases are not frequent and therefore, it is almost impossible to have two arms adequately numerous and homogenous for statistical evaluation. Thus, in the absence of solid evidence based data, the hepatologists could treat their patients with severe acute hepatitis B with lamivudine or the most potent antivirals entecavir or tenofovir.

Ursodeoxycholic acid and artesunate in the treatment of severe falciparum malaria patients with jaundice

BACKGROUND AND AIMS

Plasmodium falciparum (PF) infection can lead to severe complications. Ursodeoxycholic acid (UDCA) is increasingly used for the treatment of cholestatic liver diseases. The present study aims to determine the effects of combined UDCA and artesunate compared to placebo and artesunate on the improvement of liver tests in severe PF jaundiced patients.

METHODS

All severe PF jaundiced patients, aged > or = 15 years and diagnosed as having severe malaria according to WHO 2000 criteria, were enrolled. Patients with evidence of biliary obstruction, other cholestatic liver diseases and those who were pregnant were excluded. Patients were randomized to receive either oral UDCA or placebo for 2 weeks in additional to artesunate. All patients were admitted for at least 14 days to monitor the result of the treatment.

RESULTS

Seventy-four severe PF malaria patients with jaundice were enrolled. Both groups had similar demographic and laboratory tests, with the exception being more males in the UDCA group than in the placebo group (P = 0.04). The median of percentage change of total bilirubin and aminotransferase levels at the end of weeks 1, 2, 3 and 4 showed no difference between the two groups. Only the median of percentage change of alkaline phosphatase at the end of week one compared with the baseline values showed less increment in the UDCA group than in the placebo group (P = 0.04). No serious adverse events were seen during the 4 weeks of follow up.

CONCLUSIONS

In severe PF malaria patients with jaundice, combined therapy with UDCA and artesunate is safe, but does not significantly improve liver tests compared to placebo and artesunate.

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.

Inhibitory effects of bear bile powder on dimethylnitrosamine-induced liver fibrosis in rats

AIM: To investigate the inhibitory effect of bear bile powder on rat liver fibrosis induced by dimethylnitrosamine (DMN).

METHODS: A total of 30 rats were randomly divided into 3 groups: normal control group, model group, and bear bile group (10 in every group). The rat liver fibro-sis model was induced by peritoneal injection of DMN (10 g/L) for 4 wk. At the same time, the rats in the bear bile group received bear bile powder (400 mg/kg) orally once a day for 4 wk. Then the activities of serum alanine transaminase (ALT), aspartate transaminase (AST), and the contents of total protein (TP) were detected. Meanwhile, the pathological changes of liver tissues were observed under light microscope after HE staining, and the area density of collagenous fiber were examined. The amount and distribution of Kupffer cell (KC) and hepatic stellate cell (HSC) were detected by immunohistochemical SP method through the distribution of ED1 and α-smooth muscle actin (α-SMA).

RESULTS: Compared with that in the model group, the level of serum ALT was decreased, and AST was significantly decreased (4 370.87±1 338.60 nkat/L vs 5 741.15±1 000.20 nkat/L, P <0.05) in the bear bile group. The TP content and the ratio of liver to body weigh were increased. The area density of collagenous fiber was notably decreased (6.73±1.31 vs 9.90±1.93, P <0.01). The pathological changes were lighter, and the occurrence rate of diffused liver fibrosis was lower in the bear bile group than those in the model group. The fibrous septa became thin or disappeared, and the expressions of ED1 and α-SMA were markedly reduced in the bear bile group.

CONCLUSION: The bear bile powder can prevent DMN-induced rat liver fibrosis, and the mechanism may relate to its inhibition on the activation of the HSC and KC.

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.

Use of ursodeoxycholic acid in liver diseases

Ursodeoxycholic acid is currently the only established drug for the treatment of chronic cholestatic liver diseases. It has cytoprotective, anti-apoptotic, membrane stabilizing, anti-oxidative and immunomodulatory effects. Prolonged administration of ursodeoxycholic acid in patients with primary biliary cirrhosis (PBC) is associated with survival benefit and a delaying of liver transplantation. There is evidence that it might even prevent progression of the histologic stage of PBC. It also has a beneficial effect on primary sclerosing cholangitis, intrahepatic cholestasis of pregnancy, liver disease associated with cystic fibrosis, chronic graft versus host disease, total parenteral nutrition associated cholestasis and various pediatric cholestatic liver diseases. In the present review the current knowledge about the mechanisms of the action and role of ursodeoxycholic acid in the treatment of various liver diseases has been discussed.