An electron microscopic and morphometric study of ursodeoxycholic effect in primary biliary cirrhosis

Omega-3 Polyunsaturated Fatty Acid: A Pharmaco-Nutraceutical Approach to Improve the Responsiveness to Ursodeoxycholic Acid

Ursodeoxycholic acid (UDCA) is the first line therapy for the treatment of cholestatic and autoimmune liver diseases. Its clinical use is currently limited by a significant proportion of non-responder patients. Polyunsaturated fatty acids (n-3 PUFAs) possess important anti-inflammatory properties and protect liver cells against bile acid (BA)-induced toxicity. The present study was designed to rapidly evaluate whether combining n-3 PUFAs (i.e., eicosapentaenoic [EPA] and docosahexaenoic [DHA] acids) to UDCA would provide additional benefits when compared to the drug alone. The parameters evaluated were (i) the expression of genes governing BA synthesis, transport, and metabolism; (ii) the prevention of BA-induced apoptosis and endoplasmic reticulum (ER)-stress; and (iii) the control of BA- and LPS-dependent inflammation. In the absence of n-3 PUFAs, most of the parameters investigated were unaffected by UDCA or were only altered by the higher dose (500 µM) of the drug. By contrast, in the presence of EPA/DHA (50/50 µM), all parameters showed a strongly improved response and the lowest UDCA dosage (50 µM) provided equal or better benefits than the highest dose used alone. For example, the combination EPA/DHA + UDCA 50 µM caused comparable down-regulation of the CYP7A1 gene expression and of the BA-induced caspase 3 activity as observed with UDCA 500 µM. In conclusion, these results suggest that the addition of n-3 PUFAs to UDCA may improve the response to the drug, and that such a pharmaco-nutraceutical approach could be used in clinic to open the narrow therapeutic dose of UDCA in cholestatic liver diseases.

Serum Gas6 and Axl as non-invasive biomarkers of advanced histological stage in primary biliary cholangitis

AIM

Advanced histological stage is an important factor in individual risk stratification in patients with primary biliary cholangitis (PBC). Non-invasive biomarkers for advanced histological stage are needed. We assessed the utility of Gas6 and Axl as biomarkers for advanced histological stage in patients with PBC.

METHODS

A total of 113 biopsy-proven PBC patients and 20 healthy controls were included in this study. Serum Axl and Gas6 were measured using enzyme-linked immunosorbent assay. The Gas6 / albumin ratio and Axl / albumin ratio were also evaluated as biomarkers of histological stage.

RESULTS

Serum Axl (42.6 ng/mL vs. 30.6 ng/mL, P < 0.001) and Gas6 (21.1 ng/mL vs. 18.8 ng/mL, P = 0.007) levels in PBC patients were significantly higher than those in healthy controls. The Axl / albumin ratio was 10.4, and the Gas6 / albumin ratio was 7.6 in patients with PBC. Gas6 and Axl were significantly correlated with aspartate aminotransferase, bilirubin, albumin, and platelets. Gas6 and Axl levels in patients with an advanced Scheuer stage and an advanced Nakanuma stage were significantly higher than those in other patients. The area under the receiver operating characteristic curve (AUROC) of Axl, Gas6, Axl / albumin, and Gas6 / albumin for diagnosing Scheuer stage 4 was 0.733, 0.837, 0.845, and 0.893, respectively. The AUROC of Axl, Gas6, Axl / albumin, and Gas6 / albumin for diagnosing Nakanuma stage 4 was 0.794, 0.834, 0.869, and 0.898, respectively.

CONCLUSION

High levels of Gas6 and Axl were associated with advanced histological stage in PBC patients. Furthermore, the Gas6 / albumin ratio and the Axl / albumin ratio showed a high AUROC for diagnosing advanced histological stage.

Pharmacological interventions for primary biliary cholangitis: an attempted network meta-analysis

BACKGROUND

Primary biliary cholangitis (previously primary biliary cirrhosis) is a chronic liver disease caused by the destruction of small intra-hepatic bile ducts resulting in stasis of bile (cholestasis), liver fibrosis, and liver cirrhosis. The optimal pharmacological treatment of primary biliary cholangitis remains uncertain.

OBJECTIVES

To assess the comparative benefits and harms of different pharmacological interventions in the treatment of primary biliary cholangitis through a network meta-analysis and to generate rankings of the available pharmacological interventions according to their safety and efficacy. However, it was not possible to assess whether the potential effect modifiers were similar across different comparisons. Therefore, we did not perform the network meta-analysis, and instead, assessed the comparative benefits and harms of different interventions using standard Cochrane methodology.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), MEDLINE, Embase, Science Citation Index Expanded, World Health Organization International Clinical Trials Registry Platform, and randomised controlled trials registers to February 2017 to identify randomised clinical trials on pharmacological interventions for primary biliary cholangitis.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or publication status) in participants with primary biliary cholangitis. We excluded trials which included participants who had previously undergone liver transplantation. We considered any of the various pharmacological interventions compared with each other or with placebo or no intervention.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We calculated the odds ratio (OR) and rate ratio with 95% confidence intervals (CI) using both fixed-effect and random-effects models based on available-participant analysis with Review Manager 5. We assessed risk of bias according to Cochrane, controlled risk of random errors with Trial Sequential Analysis, and assessed the quality of the evidence using GRADE.

MAIN RESULTS

We identified 74 trials including 5902 participants that met the inclusion criteria of this review. A total of 46 trials (4274 participants) provided information for one or more outcomes. All the trials were at high risk of bias in one or more domains. Overall, all the evidence was low or very low quality. The proportion of participants with symptoms varied from 19.9% to 100% in the trials that reported this information. The proportion of participants who were antimitochondrial antibody (AMA) positive ranged from 80.8% to 100% in the trials that reported this information. It appeared that most trials included participants who had not received previous treatments or included participants regardless of the previous treatments received. The follow-up in the trials ranged from 1 to 96 months.The proportion of people with mortality (maximal follow-up) was higher in the methotrexate group versus the no intervention group (OR 8.83, 95% CI 1.01 to 76.96; 60 participants; 1 trial; low quality evidence). The proportion of people with mortality (maximal follow-up) was lower in the azathioprine group versus the no intervention group (OR 0.56, 95% CI 0.32 to 0.98; 224 participants; 2 trials; I2 = 0%; low quality evidence). However, it has to be noted that a large proportion of participants (25%) was excluded from the trial that contributed most participants to this analysis and the results were not reliable. There was no evidence of a difference in any of the remaining comparisons. The proportion of people with serious adverse events was higher in the D-penicillamine versus no intervention group (OR 28.77, 95% CI 1.57 to 526.67; 52 participants; 1 trial; low quality evidence). The proportion of people with serious adverse events was higher in the obeticholic acid plus ursodeoxycholic acid (UDCA) group versus the UDCA group (OR 3.58, 95% CI 1.02 to 12.51; 216 participants; 1 trial; low quality evidence). There was no evidence of a difference in any of the remaining comparisons for serious adverse events (proportion) or serious adverse events (number of events). None of the trials reported health-related quality of life at any time point.

FUNDING

nine trials had no special funding or were funded by hospital or charities; 31 trials were funded by pharmaceutical companies; and 34 trials provided no information on source of funding.

AUTHORS' CONCLUSIONS

Based on very low quality evidence, there is currently no evidence that any intervention is beneficial for primary biliary cholangitis. However, the follow-up periods in the trials were short and there is significant uncertainty in this issue. Further well-designed randomised clinical trials are necessary. Future randomised clinical trials ought to be adequately powered; performed in people who are generally seen in the clinic rather than in highly selected participants; employ blinding; avoid post-randomisation dropouts or planned cross-overs; should have sufficient follow-up period (e.g. five or 10 years or more); and use clinically important outcomes such as mortality, health-related quality of life, cirrhosis, decompensated cirrhosis, and liver transplantation. Alternatively, very large groups of participants should be randomised to facilitate shorter trial duration.

Clinical significance of the Scheuer histological staging system for primary biliary cholangitis in Japanese patients

BACKGROUND

Inadequate response to ursodeoxycholic acid (UDCA) is associated with unfavorable outcomes in patients with primary biliary cholangitis (PBC). We aimed to identify surrogate markers for predicting long-term prognosis and biochemical response to UDCA in patients with PBC.

PATIENTS AND METHODS

In this single-center, retrospective study, 99 patients with PBC were classified into responders (n=53) and nonresponders (n=46) based on reductions in the γ-glutamyl transpeptidase levels at 1 year after initiating UDCA therapy (Nara criteria). We assessed whether the criteria for patentability by different countries are useful in predicting the prognosis of PBC. The accuracy of Scheuer and Nakanuma staging systems in predicting prognosis and treatment response was compared.

RESULTS

Nara definition had comparable utility to the Paris-II definition for selecting patients in whom UDCA monotherapy can be safely continued. Patients at Scheuer stage 1 had a significantly better prognosis than those at Scheuer stages 3 or 4 (P<0.05 and 0.0001, respectively). Patients at Nakanuma stage 4 had decreased survival compared with those at stage 1 (P<0.05). The proportion of responders to nonresponders was significantly higher in stages 1-3 PBC than in stage 4 PBC, according to both staging systems (P<0.05 for both). All patients with Scheuer stage 4 PBC were nonresponders, whereas only 28.6% (2/7) of those with Nakanuma stage 4 PBC were responders.

CONCLUSION

The Scheuer staging system had greater utility in predicting long-term prognosis and UDCA response than the Nakanuma staging system.

Evidence-based clinical practice guidelines for liver cirrhosis 2015

The Japanese Society of Gastroenterology revised the evidence-based clinical practice guidelines for liver cirrhosis in 2015. Eighty-three clinical questions were selected, and a literature search was performed for the clinical questions with use of the MEDLINE, Cochrane, and Igaku Chuo Zasshi databases for the period between 1983 and June 2012. Manual searching of the latest important literature was added until August 2015. The guidelines were developed with use of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. This digest version in English introduces selected clinical questions and statements related to the management of liver cirrhosis and its complications. Branched-chain amino acids relieve hypoalbuminemia and hepatic encephalopathy and improve quality of life. Nucleoside analogues and peginterferon plus ribavirin combination therapy improve the prognosis of patients with hepatitis B virus related liver cirrhosis and hepatitis C related compensated liver cirrhosis, respectively, although the latter therapy may be replaced by direct-acting antivirals. For liver cirrhosis caused by primary biliary cirrhosis and active autoimmune hepatitis, urosodeoxycholic acid and steroid are recommended, respectively. The most adequate modalities for the management of variceal bleeding are the endoscopic injection sclerotherapy for esophageal varices and the balloon-occluded retrograde transvenous obliteration following endoscopic obturation with cyanoacrylate for gastric varices. Beta-blockers are useful for primary prophylaxis of esophageal variceal bleeding. The V2 receptor antagonist tolvaptan is a useful add-on therapy in careful diuretic therapy for ascites. Albumin infusion is useful for the prevention of paracentesis-induced circulatory disturbance and renal failure. In addition to disaccharides, the nonabsorbable antibiotic rifaximin is useful for the management of encephalopathy. Anticoagulation therapy is proposed for patients with acute-onset or progressive portal vein thrombosis.

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.

Ursodeoxycholic acid treatment improves hepatocyte ultrastructure in rat liver fibrosis

AIM: To examine the ultrastructural changes after ursodeoxycholic acid (UDCA) treatment in hepatocytes from experimentally induced fibrotic livers.

METHODS: Liver fibrosis was induced in male Sprague-Dawley rats with CCl₄ for 12 wk, and the rats were divided into two groups. Group I was treated with saline and group II with UDCA (25 mg/kg per day) for 4 wk. All the rats were killed at wk 16. Mitochondria, nuclei, rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER) of hepatocytes were evaluated according to a scoring system.

RESULTS: Mitochondria, nuclei, RER and SER injury scores in group II were significantly lower than those in groupI(P < 0.001).

CONCLUSION: UDCA alleviates hepatocyte organelle injury in CCl₄-induced liver fibrosis.

Concept on the pathogenesis and treatment of primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is an organ-specific autoimmune disease that predominantly affects women and is characterized by chronic, progressive destruction of small intrahepatic bile ducts with portal inflammation and ultimately fibrosis, leading to liver failure in the absence of treatment. Little is known about the etiology of PBC. PBC is characterized by anti-mitochondrial antibodies and destruction of intra-hepatic bile ducts. The serologic hallmark of PBC is the presence of auto-antibodies to mitochondria, especially to the E2 component of the pyruvate dehydrogenase complex (PDC). Current theories on the pathogenesis of PBC favor the hypothesis that the disease develops as a result of an inappropriate immune response following stimulation by an environmental or infectious agent. Some reports suggest that xenobiotics and viral infections may induce PBC. The pathogenetic mechanism is believed to be caused by a defect in immunologic tolerance, resulting in the activation and expansion of self-antigen specific T and B lymphocyte clones and the production of circulating autoantibodies in addition to a myriad of cytokines and other inflammatory mediators. This leads to ductulopenia and persistent cholestasis, by developing end-stage hepatic-cell failure. In this review are given our own and literary data about mechanisms of development of intrahepatic cholestasis and possible ways of its correction.