Anticholestatic effects of bezafibrate in patients with primary biliary cirrhosis treated with ursodeoxycholic acid

Identification of global mRNA expression profiles and comprehensive bioinformatic analyses of abnormally expressed genes in cholestatic liver disease

BACKGROUND

Cholestatic liver disease (CLD) is a highly heterogeneous hepatobiliary disease with various causes. The purpose of this research was to explore the gene expression changes throughout the course of CLD revealing potential causative molecular mechanisms and therapeutic targets.

METHODS

We established two animal models of cholestasis: 3,5-diethoxycarbonyl-1,4-dihydrocollidine feeding for 2, 4 and 6 weeks and bile duct ligation for 14 days. Using these two models, we identified differentially expressed genes (DEGs) by RNA-Seq analysis and used the newly-found knowledge of DEGs in comprehensive bioinformatic analyses to investigate key molecular events. Sequencing results were confirmed by experimental verification.

RESULTS

Our study detected overlapping DEGs in the two models, of these 568 genes were upregulated and 117 genes were downregulated. Gene Ontology analysis demonstrated that the upregulated genes were associated with the biological processes of cell adhesion, cell migration and cell motility, while the metabolic processes of various substances were enriched for the downregulated genes. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that the upregulated pathways were mainly distributed in focal adhesion, ECM-receptor interaction and amoebiasis, while downregulated pathways focused on peroxisome proliferator-activated receptor signaling pathway, metabolic pathways and primary bile acid biosynthesis. These findings were further confirmed by protein-protein interaction network modeling. Hub genes Src, Pdgfb, Col15a1, Mmp9, Egfr were selected using centralities analyses and verified by qRT-PCR.

CONCLUSION

We profiled a global mRNA landscape in CLD to promote a complete understanding of transcriptomic events of this disease, offering candidate biomarkers and therapeutic targets for the clinic.

Emerging novel treatments for autoimmune liver diseases

The etiology of autoimmune liver diseases, such as autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC), still remains largely unknown and no therapeutic agents that are able to "cure" these diseases have been developed. Although corticosteroids for AIH and ursodeoxycholic acid for PBC have been shown to significantly improve liver transplantation (LT)-free survival and are recommended as first-line drugs, treatment strategies for patients who show incomplete response to these drugs have not yet been fully established. No drug is significantly associated with long LT-free survival in PSC patients. Nevertheless, with progress in genetics, immunology, and cellular biology, several new compounds or antibodies are expected to have an effect on autoimmune liver diseases and several drugs are under consideration for clinical use. Although most clinical trials have been carried out in the USA or Europe, some are, or will be, undertaken in Japan in the future. In this review, the current standard-of-care of autoimmune liver diseases will be summarized, together with emerging novel treatments relevant to clinical practice in Japan.

Therapeutic Roles of Bile Acid Signaling in Chronic Liver Diseases

Bile acids (BAs) are the major metabolic product of cholesterol, having detergent-like activities and being responsible for absorption of lipid and lipid-soluble vitamins. In addition, it has been increasingly recognized that BAs are important signaling molecules, regulating energy metabolism and immunity. Under physiological circumstances, synthesis and transport of BAs are precisely regulated to maintain bile acid homeostasis. Disruption of bile acid homeostasis results in pathological cholestasis and metabolic liver diseases. During the last decades, BAs have been gradually recognized as an important therapeutic target for novel treatment in chronic liver diseases. This review will provide an update on the current understanding of synthesis, transport and regulation of BAs, with a focus on the therapeutic roles of bile acid signaling in chronic liver diseases.

Human-specific dual regulations of FXR-activation for reduction of fatty liver using in vitro cell culture model

Nuclear receptor farnesoid X receptor activation inhibits fatty acid synthesis through the liver X receptor-α-sterol regulatory element binding protein-1c pathway universally in animals, but also has human-specific crosstalk with the peroxisome proliferator-activated receptor-α. The effects of farnesoid X receptor-ligands on both the synthesis and degradation of fatty liver through nuclear receptor-related regulation were investigated in both human and murine hepatocytes. A fatty liver culture cell model was established using a synthetic liver X receptor-α-ligand (To901317) for both human and mouse non-neoplastic hepatocytes. The hepatocytes were exposed to natural or synthetic farnesoid X receptor-ligands (bile acids, GW4064, obeticholic acid) together with or after To901317. Cellular triglyceride accumulation was significantly inhibited by the farnesoid X receptor-ligands along with inhibition of lipogenic genes and up-regulation of farnesoid X receptor-target small heterodimer partner in both human and mouse cells. The accumulated triglyceride was significantly degraded by the farnesoid X receptor-ligands only in the human cells accompanied with the up-regulations of peroxisome proliferator-activated receptor-α and fatty acid β-oxidation. Farnesoid X receptor-ligands can be therapeutic agents for treating human fatty liver through dual effects on inhibition of lipogenesis and on enhancement of lipolysis.

Identification of a xenobiotic as a potential environmental trigger in primary biliary cholangitis

BACKGROUND & AIMS

Primary biliary cholangitis (PBC) is an autoimmune-associated chronic liver disease triggered by environmental factors, such as exposure to xenobiotics, which leads to a loss of tolerance to the lipoic acid-conjugated regions of the mitochondrial pyruvate dehydrogenase complex, typically to the E2 component. We aimed to identify xenobiotics that might be involved in the environmental triggering of PBC.

METHODS

Urban landfill and control soil samples from a region with high PBC incidence were screened for xenobiotic activities using analytical, cell-based xenobiotic receptor activation assays and toxicity screens.

RESULTS

A variety of potential xenobiotic classes were ubiquitously present, as identified by their interaction with xenobiotic receptors - aryl hydrocarbon receptor, androgen receptor and peroxisome proliferator activated receptor alpha - in cell-based screens. In contrast, xenoestrogens were present at higher levels in soil extracts from around an urban landfill. Furthermore, two landfill sampling sites contained a chemical(s) that inhibited mitochondrial oxidative phosphorylation and induced the apoptosis of a hepatic progenitor cell. The mitochondrial effect was also demonstrated in human liver cholangiocytes from three separate donors. The chemical was identified as the ionic liquid [3-methyl-1-octyl-1H-imidazol-3-ium]+ (M8OI) and the toxic effects were recapitulated using authentic pure chemical. A carboxylate-containing human hepatocyte metabolite of M8OI, bearing structural similarity to lipoic acid, was also enzymatically incorporated into the E2 component of the pyruvate dehydrogenase complex via the exogenous lipoylation pathway in vitro.

CONCLUSIONS

These results identify, for the first time, a xenobiotic in the environment that may be related to and/or be a component of an environmental trigger for PBC. Therefore, further study in experimental animal models is warranted, to determine the risk of exposure to these ionic liquids.

LAY SUMMARY

Primary biliary cholangitis is a liver disease in which most patients have antibodies to mitochondrial proteins containing lipoic acid binding site(s). This paper identified a man-made chemical present in soils around a waste site. It was then shown that this chemical was metabolized into a product with structural similarity to lipoic acid, which was capable of replacing lipoic acid in mitochondrial proteins.

Are Clinicians Ready for Safe Use of Stratified Therapy in Primary Biliary Cholangitis (PBC)? A Study of Educational Awareness

BACKGROUND

Primary Biliary Cholangitis (PBC, formerly cirrhosis), is a chronic cholestatic liver disease which until spring 2016 had a single licensed therapy, Ursodeoxycholic acid (UDCA). Approximately 30% of patients do not respond to UDCA, and are high-risk for progressing to end stage liver disease, transplantation or death. A new era of stratified medicine with second-line therapies to treat high-risk disease is emerging, with the first such second-line agent obeticholic acid recently receiving FDA and EMA approval and entering practice. Recent experience in the USA of inappropriate use and associated deaths has highlighted concerns as to whether clinicians have the knowledge to implement second-line therapies appropriately and safely.

METHODS

Online survey of knowledge regarding optimal PBC management in Gastroenterologists and Hepatologists in the USA; the first 100 completed responses from each group used for analysis.

RESULTS

80% of Hepatologists felt they were highly competent in their understanding of the importance of early diagnosis and early UDCA therapy in PBC compared with 65% of gastroenterologists. However, only 36% of Hepatologists and 30% of gastroenterologists felt competent at assessing response to UDCA. Competence in knowledge (mode of action, efficacy, and side effects) of second-line therapies and enrollment into trials was low among both groups.

CONCLUSION

Significant knowledge gaps in clinicians managing PBC presents a problem in optimizing care. It is perhaps not surprising that knowledge of emerging second-line therapies is low, however more concerning is sub-optimal use of UDCA in real-life practice and the lack of confidence at assessing treatment response which should be a routine part of clinical practice to assess risk of disease progression and will be key in delivering stratified medicine.

Novel and emerging therapies for cholestatic liver diseases

While bile acids are important for both digestion and signalling, hydrophobic bile acids can be harmful, especially when in high concentrations. Mechanisms for the protection of cholangiocytes against bile acid cytotoxicity include negative feedback loops via farnesoid X nuclear receptor (FXR) activation, the bicarbonate umbrella, cholehepatic shunting and anti-inflammatory signalling, among others. By altering or overwhelming these defence mechanisms, cholestatic diseases such as primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) can further progress to biliary cirrhosis, end-stage liver disease and death or liver transplantation. While PBC is currently treated with ursodeoxycholic acid (UDCA) and obeticholic acid (OCA), many fail treatment, and we have yet to find an effective therapy for PSC. Novel therapies under evaluation target nuclear and surface receptors including FXR, transmembrane G-protein-coupled receptor 5 (TGR5), peroxisome proliferator-activated receptor (PPAR) and pregnane X receptor (PXR). Modulation of these receptors leads to altered bile composition, decreased cytotoxicity, decreased inflammation and improved metabolism. This review summarizes our current understanding of the role of bile acids in the pathophysiology of cholestatic liver diseases, presents the rationale for already approved medical therapies and discusses novel pharmacologic therapies under investigation.

Current Treatment Options for Primary Biliary Cholangitis

Primary biliary cholangitis is a progressive, autoimmune disease of the interlobular bile ducts, leading to secondary damage of hepatocytes that may progress to cirrhosis and liver failure. Until recently, the only approved treatment was ursodeoxycholic acid. However, 40% of patients do not have an adequate response. Obeticholic acid was approved for treatment as add-on therapy in this group of patients. Off-label use of fibrates has also been reported to be effective. Several new therapies are in development and may further add to the treatment options available to patients with primary biliary cholangitis.

Role of Bile Acids and the Biliary HCO3- Umbrella in the Pathogenesis of Primary Biliary Cholangitis

The biliary HCO₃^- umbrella hypothesis states that human cholangiocytes and hepatocytes create a protective apical alkaline barrier against millimolar concentrations of potentially toxic glycine-conjugated bile salts in bile by secreting HCO₃^- into the bile duct lumen. This alkaline barrier may retain biliary bile salts in their polar, deprotonated, and membrane-impermeant state to avoid uncontrolled invasion of apolar toxic bile acids, which initiate apoptosis, autophagy and senescence. In primary biliary cholangitis, defects of the biliary HCO₃^- umbrella, leading to impaired biliary HCO₃^- secretion have been identified. Current medical therapies stabilize the putatively defective biliary HCO₃^- umbrella and improve long-term prognosis.

Editor's Highlight: Clofibrate Decreases Bile Acids in Livers of Male Mice by Increasing Biliary Bile Acid Excretion in a PPARα-Dependent Manner

Fibrates and their receptor, namely peroxisome proliferator-activated receptor α (PPARα), have been reported to regulate bile acid (BA) synthesis and transport. However, the effect of fibrate treatment and PPARα activation on BA homeostasis remains controversial. In this study, both wild-type (WT) and PPARα-null male mice were treated with clofibrate (CLOF) for 4 days to evaluate the effects of short-term PPARα activation on BA homeostasis. Although a decrease in total BAs (ΣBAs) was observed in livers of CLOF-treated WT mice, it was not observed in PPARα-null mice. CLOF-mediated decrease in ΣBAs in the liver was not likely due to the reduction in BA synthesis or BA uptake, as evidenced by an increase in the BA synthetic enzyme (Cyp7a1) and 2 BA uptake transporters (Na (+)-taurocholate cotransporting polypeptide [Ntcp] and organic anion transporting polypeptide [Oatp]1b2). Instead, the decrease in liver BAs by CLOF is largely a result of increased biliary excretion of BAs, which was associated with a significant induction of the canalicular efflux transporter (bile salt export pump [Bsep]) in the liver. The PPARα-mediated increase in Cyp7a1 in CLOF-treated WT mice was not due to farnesoid X receptor (Fxr)-small heterodimer partner (Shp) signaling in the liver, but due to suppression of Fxr- fibroblast growth factor15 signaling in the ileum. Additionally, CLOF also suppressed intestinal BA transporters (apical sodium-dependent bile acid transporter and organic solute transporterβ) and cholesterol efflux transporters (Abcg5 and Abcg8) in a PPARα-dependent manner. In summary, this study provides the first comprehensive analysis on the effect of a short-term CLOF treatment on BA homeostasis, and revealed an essential role of PPARα in regulating BA synthesis, transport and signaling.

Improving prognosis in primary biliary cholangitis - Therapeutic options and strategy

Overall survival in primary biliary cholangitis is diminished. As patients are often asymptomatic, the disease may silently progress towards cirrhosis and liver failure. Timely diagnosis and effective treatment options are of vital importance to improve the prognosis of affected patients. Ursodeoxycholic acid is the standard of care first-line therapy and is associated with a reduced risk of liver transplantation and death. Treatment with UDCA is relevant for all patients, irrespective of disease stage or biochemical response. In case of incomplete biochemical response according to internationally accepted criteria, second-line treatment should be considered to improve long-term prognosis. Ursodeoxycholic acid has been the only accepted treatment for PBC during the last decades. Recent research, however, has identified a number of new therapeutic targets and agents, including obeticholic acid, fibrates and budesonide. While these agents all qualify as potentially beneficial second-line treatment, obeticholic acid is currently the only drug specifically approved for the treatment of PBC. Although long-term follow-up studies for these agents are mostly lacking, improvement of biochemical surrogate markers of clinical outcome induced by these drugs suggests a therapeutic benefit. The authors of this review aim to provide a summary of the results of previous and current studies evaluating medical treatments, and propose a treatment strategy based on the evidence available today.

A Placebo-Controlled Trial of Bezafibrate in Primary Biliary Cholangitis

BACKGROUND

Patients with primary biliary cholangitis who have an inadequate response to therapy with ursodeoxycholic acid are at high risk for disease progression. Fibrates, which are agonists of peroxisome proliferator-activated receptors, in combination with ursodeoxycholic acid, have shown potential benefit in patients with this condition.

METHODS

In this 24-month, double-blind, placebo-controlled, phase 3 trial, we randomly assigned 100 patients who had had an inadequate response to ursodeoxycholic acid according to the Paris 2 criteria to receive bezafibrate at a daily dose of 400 mg (50 patients), or placebo (50 patients), in addition to continued treatment with ursodeoxycholic acid. The primary outcome was a complete biochemical response, which was defined as normal levels of total bilirubin, alkaline phosphatase, aminotransferases, and albumin, as well as a normal prothrombin index (a derived measure of prothrombin time), at 24 months.

RESULTS

The primary outcome occurred in 31% of the patients assigned to bezafibrate and in 0% assigned to placebo (difference, 31 percentage points; 95% confidence interval, 10 to 50; P<0.001). Normal levels of alkaline phosphatase were observed in 67% of the patients in the bezafibrate group and in 2% in the placebo group. Results regarding changes in pruritus, fatigue, and noninvasive measures of liver fibrosis, including liver stiffness and Enhanced Liver Fibrosis score, were consistent with the results of the primary outcome. Two patients in each group had complications from end-stage liver disease. The creatinine level increased 5% from baseline in the bezafibrate group and decreased 3% in the placebo group. Myalgia occurred in 20% of the patients in the bezafibrate group and in 10% in the placebo group.

CONCLUSIONS

Among patients with primary biliary cholangitis who had had an inadequate response to ursodeoxycholic acid alone, treatment with bezafibrate in addition to ursodeoxycholic acid resulted in a rate of complete biochemical response that was significantly higher than the rate with placebo and ursodeoxycholic acid therapy. (Funded by Programme Hospitalier de Recherche Clinique and Arrow Génériques; BEZURSO ClinicalTrials.gov number, NCT01654731 .).

Differences in the Serum 4β-hydroxycholesterol Levels of Patients with Chronic Hepatitis C Virus (HCV) Infection: A Possible Impact on the Efficacy and Safety of Interferon (IFN)-free Treatment

Objective Since the majority of direct-acting antivirals (DAAs) that are used in the treatment of hepatitis C virus (HCV) infection are mainly metabolized by CYP3A4, it is hypothesized that inter-individual differences in CYP3A4 activity may be associated with the bioavailability of these agents. Methods The level of serum 4β-hydroxycholesterol (4βHC), a surrogate marker of CYP3A4 activity, was determined by LC-MS/MS in samples obtained from patients with HCV infection (CHCs) as well as healthy control subjects (CTLs). Serum samples obtained from patients treated with either asunaprevir/daclatasvir (ASV/DCV) or ombitasvir/paritaprevir/ritonavir (OTV/PTV/r) were used for additional assays. Results The serum 4βHC level in CHCs was significantly higher than that in CTLs, and a gender difference was seen among CHCs. In patients treated with OTV/PTV/r, the serum 4βHC level was observed to gradually decrease during the treatment period. In the cohort treated with ASV/DCV, 4 of 83 patients showed virological treatment failure. In pretreatment testing, an Invader assay detected a low prevalence of resistance-associated variants in these four patients. The average serum concentration of DCV/ASV in the treatment-failed group tended to be lower than that in the sustained virological response (SVR) group. The pretreatment serum 4βHC level in patients with treatment failure was significantly higher than that in patients with an SVR but in whom the prevalence of resistance-associated variants was low in the pretreatment setting. Conclusion The evaluation of CYP3A4 activity by measuring 4βHC before treatment may provide additional information that can potentially be used to select cost- and efficacy-optimized treatment of HCV.

Effects of Bezafibrate on Outcome and Pruritus in Primary Biliary Cholangitis With Suboptimal Ursodeoxycholic Acid Response

OBJECTIVES

Adding fibrates improves liver biochemistries in patients with primary biliary cholangitis (PBC) and suboptimal response to ursodeoxycholic acid (UDCA). As there are no consistent data regarding the course and outcome, we have assessed the effects of the combined treatment with UDCA and bezafibrate on a long-term basis.

METHODS

A total of 48 patients (45 female) with PBC treated with UDCA and alkaline phosphatase (ALP) above 1.5 times upper normal levels (× UNL) were treated with bezafibrate (400 mg/day) plus UDCA (13-16 mg/kg/day). Changes in clinical features, liver biochemistries, and prognosis after therapy were assessed, as well as pruritus, using a visual analog scale (43 patients) and the 5-D descriptive pruritus scale.

RESULTS

After a median of 38 months, 26 patients (54%) had normalized ALP. In these patients, jaundice, pruritus, and liver stiffness was lower, and age was higher than in patients who remained with elevated ALP. Biochemical improvement was less prominent in patients without ALP normalization. Five of these patients (23%) developed events of disease progression: 1 died, 3 were transplanted, and 1 developed hepatocellular carcinoma. Partial or complete itching relief was reported in all but one case with pruritus. Itching recurrence or worsening was observed after bezafibrate discontinuation.

CONCLUSIONS

The long-term treatment with UDCA and bezafibrate results in excellent response, and is associated with a complete or partial itching relief. Incomplete ALP normalization was observed in patients with advanced disease who remained at risk for developing severe events. The combined treatment is mainly effective in patients with lower fibrosis and severity of cholestasis.

Clinical guidelines for primary sclerosing cholangitis 2017

BACKGROUND

Primary sclerosing cholangitis (PSC) is relatively rare disease and pathogenesis and methods of treatments were still not established. Then, we had conducted the making clinical guidelines to manage patients with PSC based on the literature review and expert opinions. These clinical guidelines were made for the medical doctors on the management of PSC, except child case of PSC.

METHODS

We had employed modified Delphi method. The production committee decided guidelines, strength of recommendations and evidence level after reviewed literatures systematically, and The Expert panel evaluated those. The Scientific Committee of the Japan Biliary Association (JBA) evaluated revised guidelines, and the Public comments were collected on web site of JBA.

RESULTS

We had made 16 guidelines about epidemiology/pathophysiology, diagnostics, therapy and prognosis. Also, we had made both diagnostic and therapeutic flow chart.

CONCLUSIONS

We hope that these guidelines will contribute to the improvement and development of the medical care of PSC.

Treatment of primary biliary cholangitis ursodeoxycholic acid non-responders: A systematic review

BACKGROUND

Primary biliary cholangitis (PBC), formerly known as primary biliary cirrhosis, is a chronic cholestatic liver disease characterized by an immune mediated destruction of intrahepatic bile ducts. Ursodeoxycholic acid (UDCA) has been the primary medication for the treatment of PBC, resulting in improved liver tests, resolution of symptoms and increased transplant free survival. However, not all patients respond to UDCA. The aim of this systematic review is to provide an evidence based assessment of the medications that have been studied in patients who are refractory to UDCA.

METHODS

We performed a systematic literature search on MEDLINE and the Cochrane Database of Systematic Reviews of the published literature. A total of 23 articles fulfilling our inclusion criteria were found.

RESULTS

Several studies have shown an improvement in liver biochemistries with the use of obeticholic acid in conjunction with UDCA. Fibrates, including fenofibrate and bezafibrate, have evidence supporting benefit in this population but need more robust studies to confirm these observational results. Neither obeticholic acid nor fibrates have shown to increase transplant free survival. While there may be some benefit with methotrexate, colchicine, budesonide, mycophenolate mofetil and azathioprine, these findings were not consistent and the benefits were marginal. Further investigation is needed.

CONCLUSION

In patients with PBC refractory to UDCA, obeticholic acid or a fibrate is a reasonable choice as an adjunctive treatment to UDCA. Further investigation with randomized controlled trials is needed to provide high quality evidence to formulate standardized therapies in this difficult to treat population.

Primary biliary cholangitis: a comprehensive overview

Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by biliary destruction, progressive cholestasis, and potentially liver cirrhosis. Patients develop a well-orchestrated immune reaction, both innate and adaptive, against mitochondrial antigens that specifically targets intrahepatic biliary cells. A puzzling feature of PBC is that the immune attack is predominantly organ specific, although the mitochondrial autoantigens are found in all nucleated cells. The disease results from a combination of genetic and environmental risk factors; however, the exact pathogenesis remains unclear. Serologically, PBC is characterized by presence of antimitochondrial antibodies, which are present in 90-95 % of patients and are often detectable years before clinical signs appear. Like other complex disorders, PBC is heterogeneous in its presentation, symptomatology, disease progression, and response to therapy. A significant number of patients develop end-stage liver disease and eventually require liver transplantation. Recent studies from large international cohorts have better identified prognostic factors, suggesting a change in patient management based on risk stratification. Therapeutic options are changing. In this review we discuss data on the autoimmune responses and treatment of the disease.

An Update on the Treatment and Follow-up of Patients with Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by chronic granulomatous lymphocytic cholangitis of the small bile ducts. PBC was a leading indication for liver transplant in the United States; with early diagnosis and treatment, the majority of patients with PBC have a normal life expectancy. Pathogenesis involves inflammatory damage of bile duct epithelium secondary to innate and adaptive immune responses, and toxicity from accumulated bile acids. Cholestasis and disease progression can lead to cirrhosis. Extrahepatic complications include dyslipidemia, metabolic bone disease, and fat-soluble vitamin deficiency. Ursodeoxycholic acid is a well-established therapy. Novel targeted therapeutics are being developed.

Inhibition of JNK signalling mediates PPARα-dependent protection against intrahepatic cholestasis by fenofibrate

BACKGROUND AND PURPOSE

Fenofibrate, a PPARα agonist, is the most widely prescribed drug for treating hyperlipidaemia. Although fibrate drugs are reported to be beneficial for cholestasis, their underlying mechanism has not been determined.

EXPERIMENTAL APPROACH

Wild-type mice and Pparα-null mice were pretreated orally with fenofibrate for 3 days, following which α-naphthylisothiocyanate (ANIT) was administered to induce cholestasis. The PPARα agonist WY14643 and JNK inhibitor SP600125 were used to determine the role of PPARα and the JNK pathway, respectively, in cholestatic liver injury. The same fenofibrate regimen was applied to investigate its beneficial effects on sclerosing cholangitis in a DDC-induced cholestatic model.

KEY RESULTS

Fenofibrate, 25 mg·kg^-1 twice a day, totally attenuated ANIT-induced cholestasis and liver injury as indicated by biochemical and histological analyses. This protection occurred in wild-type, but not in Pparα-null, mice. Alterations in bile acid synthesis and transport were found to be an adaptive response rather than a direct effect of fenofibrate. WY14643 attenuated ANIT-induced cholestasis and liver injury coincident with inhibition of JNK signalling. Although SP600125 did not affect cholestasis, it inhibited liver injury in the ANIT model when the dose of fenofibrate used was ineffective. Fenofibrate was also revealed to have a beneficial effect in the sclerosing cholangitis model.

CONCLUSIONS AND IMPLICATIONS

These data suggest that the protective effects of fenofibrate against cholestasis-induced hepatic injury are dependent on PPARα and fenofibrate dose, and are mediated through inhibition of JNK signalling. This mechanism of fenofibrate protection against intrahepatic cholestasis may offer additional therapeutic opportunities for cholestatic liver diseases.

In vitro cytogenetic toxicity of bezafibrate in human peripheral blood lymphocytes

Bezafibrate (BF) is a peroxisome proliferator-activated receptor (PPAR) agonist used as a lipid-lowering agent to treat both the familial or acquired combined forms of hyperlipidemia. BF is the only available fibrate drug that acts on all PPAR subtypes of α, β, and δ. Although there are studies that indicate a genotoxic potential associated with the use of fibrates, to our knowledge, the genotoxicity of BF in human peripheral blood lymphocytes has not been studied. In the present study, the genotoxic potential of BF was evaluated using chromosome aberration (CA) and micronucleus (MN) assays in peripheral blood lymphocytes of healthy human subjects. In addition, a high performance liquid chromatography (HPLC) method was used to identify and quantitate the drug passage into the cells. Human peripheral blood lymphocytes were exposed to four different concentrations (100, 175, 250 and 325 μg/mL) of BF for 24- and 48-h treatment periods. As shown by HPLC, in spite of significant passage of BF into human peripheral blood lymphocytes in 24- and 48-h treatment periods, BF was not found to increase the CA and MN frequency. On the other hand, exposing cells to BF for 24- and 48-h treatment periods caused significant concentration-dependent decreases in the mitotic index (r = -0.995, p < 0.01 for 24-h; r = -0.992, p < 0.01 for 48-h) and nuclear division index (r = -0.990, p < 0.01 for 24-h; r = -0.981, p < 0.01 for 48-h). Our results suggest that BF has cytotoxic effect on cultured human peripheral blood lymphocytes.

Fibrates for the treatment of cholestatic itch (FITCH): study protocol for a randomized controlled trial

BACKGROUND

Pruritus (itch) is a frequent, burdensome and difficult-to-treat symptom in patients with cholestasis. Fibrates are currently under investigation for the treatment of primary biliary cholangitis in patients with a suboptimal response to ursodeoxycholic acid. Moreover, there is empirical evidence for a possible antipruritic effect. We aim to prove this in a randomized controlled trial, including patients with cholestatic liver diseases other than primary biliary cholangitis that are accompanied by pruritus.

METHODS

A multicenter investigator-initiated, double-blind, randomized placebo-controlled trial to evaluate the effect of bezafibrate on cholestatic pruritus in 84 adult patients with primary biliary cholangitis or primary/secondary sclerosing cholangitis. Primary outcome is the proportion of patients with a reduction of itch intensity of 50% or more (measured on a Visual Analog Scale) after 21 days of treatment with bezafibrate 400 mg qid or placebo. Secondary outcomes include the effect of bezafibrate on a five-dimensional itch score, liver disease-specific quality of life, serum liver tests and autotaxin activity. Safety will be evaluated through serum parameters for kidney function and rhabdomyolysis as well as precise recording of (serious) adverse events. We provide a schematic overview of the study protocol and describe the methods used to recruit and randomize patients, collect and handle data and perform statistical analyses.

DISCUSSION

Given its favorable safety profile and anticholestatic properties, bezafibrate may become the new first-line treatment option for treating cholestatic pruritus.

TRIAL REGISTRATION

Netherlands Trial Register, ID: NCT02701166 . Registered on 2 March 2016; Netherlands Trial Register, ID: NTR5436 . Registered on 3 August 2015.

Upregulation of PDZK1 by Calculus Bovis Sativus May Play an Important Role in Restoring Biliary Transport Function in Intrahepatic Cholestasis

Intrahepatic cholestasis is a main cause of hepatic accumulation of bile acids leading to liver injury, fibrosis, and liver failure. Our previous studies proved that Calculus Bovis Sativus (CBS) can restore biliary transport function through upregulating the multidrug resistance-associated protein 2 (MRP2) and breast cancer resistance protein (BCRP) in 17α-ethynylestradiol- (EE-) induced intrahepatic cholestasis rats. The regulation mechanism of CBS on these transporters, however, remains unclear. This study was designed to evaluate the possible relationship between the effect of CBS on transport activities and the regulation of CBS on the expression of PDZK1, a mainly scaffold protein which can regulate MRP2 and BCRP. Intrahepatic cholestasis model was induced in rats with injection of EE for five consecutive days and then the biliary excretion rates and cumulative biliary excretions were measured. The mRNA and protein expression levels of PDZK1 were detected by reverse transcription-quantitative real-time polymerase chain reaction, western blot, and immunohistochemical analysis. When treated with CBS, cumulative biliary excretions and mRNA and protein expressions of PDZK1 were significantly increased in intrahepatic cholestasis rats. This study demonstrated that CBS exerted a beneficial effect on EE-induced intrahepatic cholestasis rats by restoring biliary transport function, which may result from the upregulation of PDZK1 expression.

Primary biliary cholangitis: new treatments for an old disease

Primary biliary cholangitis (PBC) is an immunological condition that causes a significant health disturbance and dramatically reduces the quality of life for those affected with the disease. It is a potentially fatal disease that can lead to multiple hepatic and extrahepatic complications. Having adequate therapeutic interventions that can improve the course of the disease is imperative in reducing the associated morbidity and mortality. Ursodeoxycholic acid (UDCA) is the gold standard therapy. However, it has been associated with suboptimal response rates in a significant proportion of patients. Despite UDCA, approximately 35%-40% of individuals with PBC still experience a progression of the disease, leading to liver failure and requiring liver transplantation. Recent studies of new pharmacological approaches have shown beneficial outcomes. Some of these agents can now be applied to a clinical scenario. In this review article, we will outline the new and emerging treatments for PBC.

Management of cholestatic disease in 2017

Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are the most frequent chronic cholestatic liver diseases and serve as model diseases to discuss the management of cholestasis in 2017 in the lecture that is summarized in this report. PBC and PSC are characterized by inflammation and fibrosis of small intrahepatic (PBC) or larger intra- and/or extrahepatic (PSC) bile ducts. Bile duct damage leads to cholestasis and can progress to liver fibrosis and even cirrhosis. Various genetic, environmental and endogenous factors may contribute to the development of chronic cholestatic liver diseases, but the exact pathogenesis of PBC and PSC has not been clarified. Ursodeoxycholic acid (UDCA) is the standard treatment of PBC and is used also for other cholestatic conditions including PSC, and it exerts anticholestatic effects at adequate doses. Novel anticholestatic therapeutic options for patients not adequately responding to UDCA are under development or have, like obeticholic acid, already been proven to have efficacy when combined with UDCA in the treatment of PBC. The future role of immunomodulating/immunosuppressive drug regimens must be critically reviewed.

Proposed therapies in primary biliary cholangitis

Primary biliary cholangitis (PBC), previously known as primary biliary cirrhosis, is a model autoimmune disease with chronic cholestasis characterized by the hallmark of anti-mitochondrial antibodies and treated with ursodeoxycholic acid (UDCA). However, approximately 20-40% of patients incompletely respond to UDCA and have an increased risk of disease progression. Although there have been significant advances in the immunobiology of PBC, these have yet to be translated into newer therapeutic modalities. Current approaches to controlling the immune response include broad immunosuppression with corticosteroids as well as targeted therapies directed against T and B cells. In contrast, ameliorating cholestasis is the focus of other therapies in development, including obeticholic acid. In this article the authors will discuss ongoing clinical trials and, in particular, the rationale for choosing agents that may effectively target the aberrant immune response.

Emerging drugs for the treatment of Primary Biliary Cholangitis

INTRODUCTION

Primary biliary cholangitis (PBC) is an autoimmune chronic disease of the liver that can progress to cirrhosis and hepatocellular carcinoma. It affects approximately 1 in 4,000 with a 10:1 female to male ratio. The diagnosis of PBC can be made based on serum antimitochondrial antibodies (AMA) in a patient with abnormally high serum alkaline phosphatase after ruling out other causes of cholestasis and biliary obstruction. Genome-wide association studies have revealed several human leukocyte antigen (HLA) and non-HLA risk loci in PBC, and complex environmental-host immunogenetic interactions are believed to underlie the etiopathogenesis of the disease. Fatigue and pruritus are the most common and often problematic symptoms; although often mild, these can be severe and life-alternating in a subset of patients. Ursodeoxycholic acid (UDCA) is the only drug approved by the United States Food and Drug Administration for the treatment of PBC. Clinical trials have shown that UDCA significantly improves transplant-free survival. However, nearly 40% of PBC patients do not respond adequately to PBC and are at higher risk for serious complications when compared to PBC patients with complete response to UDCA.

AREAS COVERED

Here we provide a detailed discussion regarding novel therapeutic agents and potential areas for further investigation in PBC-related research.

EXPERT OPINION

Results of ongoing clinical trials and emerging treatment paradigms for PBC will likely further improve medical management of this disorder in the near future.

Nuclear Receptors as Therapeutic Targets in Liver Disease: Are We There Yet?

Nuclear receptors (NR) are ligand-modulated transcription factors that play diverse roles in cell differentiation, development, proliferation, and metabolism and are associated with numerous liver pathologies such as cancer, steatosis, inflammation, fibrosis, cholestasis, and xenobiotic/drug-induced liver injury. The network of target proteins associated with NRs is extremely complex, comprising coregulators, small noncoding microRNAs, and long noncoding RNAs. The importance of NRs as targets of liver disease is exemplified by the number of NR ligands that are currently used in the clinics or in clinical trials with promising results. Understanding the regulation by NR during pathophysiological conditions, and identifying ligands for orphan NR, points to a potential therapeutic approach for patients with liver diseases. An overview of complex NR metabolic networks and their pharmacological implications in liver disease is presented here.

Therapeutic advances for primary biliary cholangitis: the old and the new

Primary biliary cholangitis (PBC, primary biliary cirrhosis) is an autoimmune cholestatic liver disease characterized by chronic nonsuppurative destructive cholangitis and the presence of serum antimitochondrial antibodies. Ursodeoxycholic acid is the only drug approved by the US Food and Drug Administration to treat PBC. However, one-third of patients show incomplete responses to ursodeoxycholic acid and a poor prognosis. A number of old and new medications have been used in these patients, such as fibrates, glucocorticoids, immunosuppressants, obeticholic acid, mesenchymal stem cells, biological agents (anti-interleukin-12, cytotoxic T-lymphocyte antigen 4 immunoglobulin, anti-CD20), and antifibrotic drugs. This article reviews the therapeutic advances of these old and new medications in patients with PBC.

A functional classification of ABCB4 variations causing progressive familial intrahepatic cholestasis type 3

Progressive familial intrahepatic cholestasis type 3 is caused by biallelic variations of ABCB4, most often (≥70%) missense. In this study, we examined the effects of 12 missense variations identified in progressive familial intrahepatic cholestasis type 3 patients. We classified these variations on the basis of the defects thus identified and explored potential rescue of trafficking-defective mutants by pharmacological means. Variations were reproduced in the ABCB4 complementary DNA and the mutants, thus obtained, expressed in HepG2 and HEK293 cells. Three mutants were either fully (I541F and L556R) or largely (Q855L) retained in the endoplasmic reticulum, in an immature form. Rescue of the defect, i.e., increase in the mature form at the bile canaliculi, was obtained by cell treatments with cyclosporin A or C and, to a lesser extent, B, D, or H. Five mutations with little or no effect on ABCB4 expression at the bile canaliculi caused a decrease (F357L, T775M, and G954S) or almost absence (S346I and P726L) of phosphatidylcholine secretion. Two mutants (T424A and N510S) were normally processed and expressed at the bile canaliculi, but their stability was reduced. We found no defect of the T175A mutant or of R652G, previously described as a polymorphism. In patients, the most severe phenotypes appreciated by the duration of transplant-free survival were caused by ABCB4 variants that were markedly retained in the endoplasmic reticulum and expressed in a homozygous status.

CONCLUSION

ABCB4 variations can be classified as follows: nonsense variations (I) and, on the basis of current findings, missense variations that primarily affect the maturation (II), activity (III), or stability (IV) of the protein or have no detectable effect (V); this classification provides a strong basis for the development of genotype-based therapies.

Recent advances in understanding and managing cholestasis

Cholestatic liver diseases are hereditary or acquired disorders with impaired hepatic excretion and enterohepatic circulation of bile acids and other cholephiles. The distinct pathological mechanisms, particularly for the acquired forms of cholestasis, are not fully revealed, but advances in the understanding of the molecular mechanisms and identification of key regulatory mechanisms of the enterohepatic circulation of bile acids have unraveled common and central mechanisms, which can be pharmacologically targeted. This overview focuses on the central roles of farnesoid X receptor, fibroblast growth factor 19, and apical sodium-dependent bile acid transporter for the enterohepatic circulation of bile acids and their potential as new drug targets for the treatment of cholestatic liver disease.

It is time to change primary biliary cirrhosis (PBC): New nomenclature from "cirrhosis" to "cholangitis", and upcoming treatment based on unveiling pathology

Primary biliary cirrhosis (PBC) is a chronic, organ-specific, autoimmune liver disease characterized by progressive cholestasis, eventually leading to cirrhosis. Several lines of evidence have revealed a crucial role of adaptive as well as innate immune responses in the etiopathogenesis of PBC, and more recently, the biology of bile duct cells and genome-wide association studies (GWAS) demonstrated several key molecules and pathways in this enigmatic disease. Although ursodeoxycholic acid (UDCA) has been the only approved drug for PBC with clinical evidences for improvement of long-term outcomes, a substantial population have suboptimal responses to UDCA, resulting in unfavorable outcomes. In this regard, second-line treatment for patients refractory to UDCA is strongly awaited. In Japan, bezafibrate (BF) has been frequently used for this purpose, yet recent clinical trials failed to clearly demonstrate clinical efficacy of BF. Novel pharmacotherapies targeted to key molecules and pathways in PBC are upcoming. Finally, we sincerely call on all members of the Japan Society of Hepatology to use from this moment on the name "primary biliary cholangitis" for the disease known by its abbreviation PBC, in keeping with a very recent global agreement.

Novel Therapies on Primary Biliary Cirrhosis

All patients with primary biliary cirrhosis (PBC) and abnormal liver biochemistry should be considered for specific therapy. Ursodeoxycholic acid (UDCA) is the only FDA-approved drug for treating PBC. Approximately 40% of patients with PBC respond incompletely to treatment with UDCA, thus having increased risk of death or need for liver transplantation. No second-line therapies for patients with inadequate response to UDCA therapy have been approved. This review provides a current perspective on potential new approaches to treatment in PBC, and highlights some of the challenges we face in evaluating and effectively implementing those treatments.

New therapies for primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is a rare inflammatory liver disease for which ursodeoxycholic acid (UDCA) is the only therapy approved by the U.S. Food and Drug Administration. Patients with a biochemical response to UDCA therapy have a similar survival rate compared to the general population. However, up to 40% of PBC patients do not achieve a complete response to UDCA, have an increased risk of liver-related death and liver transplantation, and represent a persistent medical need for new therapies. Several novel drugs have recently been studied and show potential efficacy in PBC. Obeticholic acid, a farnesoid X receptor agonist, has been tested in phase II trials and initial results after 1 year in a phase III international trial suggest that it may be effective in achieving a biochemical response in approximately 40% of patients who do not completely respond to UDCA. Several small studies on fibrates have suggested that they may have efficacy, but larger studies are needed. Surprisingly, results of immunomodulators and biologics have not yet been able to demonstrate efficacy, but new approaches have shown promise in animal models and their translation to human clinical trials are awaited.

Systematic review and meta-analysis: bezafibrate in patients with primary biliary cirrhosis

BACKGROUND AND AIM

Ursodeoxycholic acid (UDCA) is the standard treatment for primary biliary cirrhosis (PBC), but not all cases respond well. Evidence has shown that combination therapy of UDCA with bezafibrate significantly improved liver function. A meta-analysis was performed to assess the efficacy and safety of UDCA and bezafibrate combination therapy in the treatment of PBC.

RESULTS

Nine trials, with a total of 269 patients, were included in the analysis. The bias risk of these trials was high. Compared with UDCA alone, the combination with bezafibrate improved the Mayo risk score (mean difference [MD], 0.60; 95% confidence interval [CI], 0.25-0.95; P=0.0008) and liver biochemistry: alkaline phosphatase (MD, -238.21 IU/L; 95% CI, -280.83 to -195.60; P<0.00001); gamma-glutamyltransferase (MD, -38.23 IU/L; 95% CI, -50.16 to -25.85; P<0.00001); immunoglobulin M (MD, -128.63 IU/L; 95% CI, -151.55 to -105.71; P<0.00001); bilirubin (MD, -0.20 mg/dL; 95% CI, -0.33 to -0.07; P=0.002); triglycerides (MD, -26.84 mg/dL; 95% CI, -36.51 to -17.17; P<0.0001); total cholesterol (MD, -21.58 mg/dL; 95% CI, -30.81 to -12.34; P<0.0001), and serum alanine aminotransferase (MD, -10.24 IU/L; 95% CI, -12.65 to -78.5; P<0.00001). However, combination therapy showed no significant differences in the incidence of all-cause mortality or pruritus, and may have resulted in more adverse events (risk ratio [RR], 0.22; 95% CI, 0.07-0.67; P=0.008).

CONCLUSION

Combination therapy improved liver biochemistry and the prognosis of PBC, but did not improve clinical symptoms or incidence of death. Attention should be paid to adverse events when using bezafibrate.

Current Concepts in Primary Biliary Cirrhosis and Primary Sclerosing Cholangitis

Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are chronic, cholestatic diseases of the liver with common clinical manifestations. Early diagnosis and treatment of PBC slows progression and decreases the need for transplant. However, one-third of patients will progress regardless of treatment. Bilirubin <1.0 and alkaline phosphatase <2.0 x the upper limit of normal at 1 year after treatment appear to predict 10-year survival. Ursodeoxycholic acid (UDCA) is the recommended treatment for PBC, and recent studies with obeticholic acid showed promising results for UDCA non-responders. Unlike PBC, no therapy has been shown to alter the natural history of PSC. The recommended initial diagnostic test for PSC is magnetic resonance cholangiopancreatography, typically showing bile duct wall thickening, focal bile duct dilatation, and saccular dilatation of the intra- and/or extrahepatic bile ducts. Immunoglobulin 4-associated cholangitis must be excluded when considering the diagnosis of PSC, to allow for proper treatment, and monitoring of disease progression. In addition to the lack of therapy, PSC is a pre-malignant condition and close surveillance is indicated.

Primary biliary cirrhosis: From bench to bedside

Primary biliary cirrhosis (PBC) is a chronic non-suppurative destructive intrahepatic cholangitis leading to cirrhosis after a protractive non cirrhotic stage. The etiology and pathogenesis are largely unknown and autoimmne mechanisms have been implicated to explain the pathological lesions. Many epitopes and autoantigens have been reported as crucial in the pathophysiology of the disease and T and B cells abnormalities have been described, the exact pathways leading to the destruction of small intrahepatic ductules are mostly speculative. In this review we examined the various epidemiologal and geoepidemiological data as well as the complex pathogenetic aspects of this disease, focusing on recent in vivo and in vitro studies in this field. Initiation and progression of PBC is believed to be a multifactorial process with strong infuences from the patient’s genetic background and by various environmental factors. The role of innate and adaptive immunity, including cytokines, chemokines, macrophages and the involvement of apoptosis and reactive oxygen species are outlined in detailed. The current pathogenetic aspects are presented and a novel pathogenetic theory unifying the accumulated clinical information with in vitro and in vivo data is formulated. A review of clinical manifestations and immunological and pathological diagnosis was presented. Treatment modalities, including the multiple mechanisms of action of ursodeoxycholate were finally discussed.

Fibrates and cholestasis

Cholestasis, including primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC), results from an impairment or disruption of bile production and causes intracellular retention of toxic bile constituents, including bile salts. If left untreated, cholestasis leads to liver fibrosis and cirrhosis, which eventually results in liver failure and the need for liver transplantation. Currently, the only therapeutic option available for these patients is ursodeoxycholic acid (UDCA), which slows the progression of PBC, particularly in stage I and II of the disease. However, some patients have an incomplete response to UDCA therapy, whereas other, more advanced cases often remain unresponsive. For PSC, UDCA therapy does not improve survival, and recommendations for its use remain controversial. These considerations emphasize the need for alternative therapies. Hepatic transporters, located along basolateral (sinusoidal) and apical (canalicular) membranes of hepatocytes, are integral determinants of bile formation and secretion. Nuclear receptors (NRs) are critically involved in the regulation of these hepatic transporters and are natural targets for therapy of cholestatic liver diseases. One of these NRs is peroxisome proliferator-activated receptor alpha (PPARα), which plays a central role in maintaining cholesterol, lipid, and bile acid homeostasis by regulating genes responsible for bile acid synthesis and transport in humans, including cytochrome P450 (CYP) isoform 7A1 (CYP7A1), CYP27A1, CYP8B1, uridine 5'-diphospho-glucuronosyltransferase 1A1, 1A3, 1A4, 1A6, hydroxysteroid sulfotransferase enzyme 2A1, multidrug resistance protein 3, and apical sodium-dependent bile salt transporter. Expression of many of these genes is altered in cholestatic liver diseases, but few have been extensively studied or had the mechanism of PPARα effect identified. In this review, we examine what is known about these mechanisms and consider the rationale for the use of PPARα ligand therapy, such as fenofibrate, in various cholestatic liver disorders.

Liver alkaline phosphatase: a missing link between choleresis and biliary inflammation

Several lines of evidence show that serum alkaline phosphatase (AP) is not only a signpost of cholestasis but also a surrogate marker of the severity of primary biliary cirrhosis and primary sclerosing cholangitis. In the present opinion article, we review and discuss the putative role of liver AP in health and in cholestatic diseases. In inflammatory cholestatic conditions, loss of activity of liver AP (resulting from its relocation from canaliculi and the acidic milieu) might promote hyper-adenosine triphosphate-bilia, lipopolysaccharide overload, and subsequent exacerbation and perpetuation of inflammation. Drugs that can restore the polarity of hepatocytes and canalicular export of bile acids or act as bile alkalinity modifiers are predicted to exert anti-inflammatory effects and to benefit both primary biliary cirrhosis and primary sclerosing cholangitis. Oral administration of intestinal AP could be a valid therapeutic intervention that deserves further study under experimental conditions as well as in human diseases. Overall, the key role of the liver microenvironment that might shape the different facets of the inflammatory processes in fibrosing cholangiopathies is highlighted.

Fenofibrate is effective adjunctive therapy in the treatment of primary biliary cirrhosis: A meta-analysis

BACKGROUND AND AIM

Fenofibrate is a potential novel therapy for primary biliary cirrhosis (PBC). We performed a systematic review and a meta-analysis of studies of fenofibrate in PBC.

METHODS

Electronic database search was performed for relevant studies. A search of abstracts presented in the main scientific meetings in the field and articles in press was also performed. Random effect model was used to pool the effect size across studies for changes in alkaline phosphatase, GGT, bilirubin and IgM levels before and after treatment and the overall rate of complete response to fenofibrate therapy.

RESULTS

Six studies with 102 patients met the inclusion criteria. All studies were case series and in all, patients who had no or incomplete response to UDCA had fenofibrate added at a dose of 100-200mg daily. Treatment duration ranged from 8-100weeks. Treatment with fenofibrate was associated with a significant decrease in alkaline phosphatase (-114IU/L, 95% CI: -152 to -76, P<0.0001); a significant decrease in GGT level (-92IU/L, 95% CI: -149 to -43; P=0.0004); significant decrease in total bilirubin (-0.11mg/dL, 95% CI: -0.18 to -0.08; P=0.0008); and a significant decrease in IgM level (-88mg/dL, 95% CI: -119 to -58; P<0.0001). The complete response rate was 69% (95% CI: 53-82%) with an odds ratio of 82.8 (95% CI: 21.6-317.2; P=0.024) while on fenofibrate.

CONCLUSIONS

Fenofibrate at doses of 100-200mg daily appears to be effective adjunctive therapy in PBC patients who had no or incomplete response to UDCA. There is a critical need for larger scale randomized trials to determine its effect on liver-related morbidity and mortality (or progression towards end-stage disease).

Biochemical responses to bezafibrate improve long-term outcome in asymptomatic patients with primary biliary cirrhosis refractory to UDCA

BACKGROUND

Bezafibrate is reported to have biochemical efficacy for patients with primary biliary cirrhosis (PBC) refractory to ursodeoxycholic acid (UDCA), yet the long-term effect is still unknown. In Japan, nationwide surveys of PBC have been performed since 1980. In the current study, we retrospectively examined whether response to bezafibrate treatment is associated with the long-term outcomes using this large-scale database.

METHODS

Among 7,376 patients in the database, we enrolled patients who were treated with UDCA at 13-15 mg/kg per day and followed up for at least 2 years after diagnosis. Bezafibrate (400 mg/day) was administered in addition to UDCA when biochemical response to UDCA was not optimal. Response to bezafibrate treatment was determined by serum alanine transaminase (ALT) levels within 2-3 years or at the earliest point thereafter from the commencement of bezafibrate treatment.

RESULTS

We enrolled 1,121 PBC patients, and the observational period was 6.1 ± 3.4 years. Among the PBC patients, 835 were asymptomatic, defined as no liver-related symptoms at the baseline. In asymptomatic PBC patients, multivariate analysis indicated that ALT response to bezafibrate treatment was significantly associated with the presence of liver-related symptoms at the end of observation [hazard ratio 1.46 (95 % confidence interval 1.01-2.13), P = 0.048]. The cumulative liver-related-symptoms-free rate of patients treated with bezafibrate and who had a normal ALT level was significantly higher than that of those treated with bezafibrate and who had an elevated ALT level (P < 0.001), and was comparable to that of those who received UDCA monotherapy.

CONCLUSION

These results suggested that normalization of ALT levels with additional bezafibrate treatment significantly decreased the rate of occurrence of liver-related symptoms in asymptomatic PBC patients with suboptimal response to UDCA.

The Cholangiopathies

Cholangiocytes (ie, the epithelial cells that line the bile ducts) are an important subset of liver cells. They are actively involved in the modification of bile volume and composition, are activated by interactions with endogenous and exogenous stimuli (eg, microorganisms, drugs), and participate in liver injury and repair. The term cholangiopathies refers to a category of chronic liver diseases that share a central target: the cholangiocyte. The cholangiopathies account for substantial morbidity and mortality given their progressive nature, the challenges associated with clinical management, and the lack of effective medical therapies. Thus, cholangiopathies usually result in end-stage liver disease requiring liver transplant to extend survival. Approximately 16% of all liver transplants performed in the United States between 1988 and 2014 were for cholangiopathies. For all these reasons, cholangiopathies are an economic burden on patients, their families, and society. This review offers a concise summary of the biology of cholangiocytes and describes a conceptual framework for development of the cholangiopathies. We also present the recent progress made in understanding the pathogenesis of and how this knowledge has influenced therapies for the 6 common cholangiopathies-primary biliary cirrhosis, primary sclerosing cholangitis, cystic fibrosis involving the liver, biliary atresia, polycystic liver disease, and cholangiocarcinoma-because the latest scientific progress in the field concerns these conditions. We performed a search of the literature in PubMed for published papers using the following terms: cholangiocytes, biliary epithelia, cholestasis, cholangiopathy, and biliary disease. Studies had to be published in the past 5 years (from June 1, 2009, through May 31, 2014), and non-English studies were excluded.

Nuclear receptors in acute and chronic cholestasis

BACKGROUND

Nuclear receptors (NRs) form a family of 48 members. NRs control hepatic processes such as bile acid homeostasis, lipid metabolism and mechanisms involved in fibrosis and inflammation. Due to their central role in the regulation of hepatoprotective mechanisms, NRs are promising therapeutic targets in cholestatic disorders.

KEY MESSAGES

NRs can be classified into five different physiological clusters. NRs from the 'bile acids and xenobiotic metabolism' and from the 'lipid metabolism and energy homeostasis' clusters are strongly expressed in the liver. Furthermore, NRs from these clusters, such as farnesoid X receptor α (FXRα), pregnane X receptor (PXR) and peroxisome proliferator-activated receptors (PPARs), have been associated with the pathogenesis and the progression of cholestasis. The latter observation is also true for vitamin D receptor (VDR), which is barely detectable in the whole liver, but has been linked to cholestatic diseases. Involvement of VDR in cholestasis is ascribed to a strong expression in nonparenchymal liver cells, such as biliary epithelial cells, Kupffer cells and hepatic stellate cells. Likewise, NRs from other physiological clusters with low hepatic expression, such as estrogen receptor α (ERα) or reverse-Erb α/β (REV-ERB α/β), may also control pathophysiological processes in cholestasis.

CONCLUSIONS

In this review, we will describe the impact of individual NRs on cholestasis. We will then discuss the potential role of these transcription factors as therapeutic targets.