Advances in Hepatology The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. IgG4 Related Sclerosing Cholangitis Mon, 10 Nov 2014 12:34:52 +0000 IgG4 related disease (IgG4-RD) is a multisystemic disorder which has only recently been recognized. IgG4 related sclerosing cholangitis (IgG4-SC) is the biliary manifestation of the disease, often in association with autoimmune pancreatitis (AIP). In this review, we provide an overview of IgG4-RD, with a focus on the biliary manifestations. In particular, we describe the important differential diagnoses of IgG4-SC that need to be considered, namely, primary sclerosing cholangitis (PSC) and cholangiocarcinoma, and provide a management algorithm. Finally, we highlight future directions and unanswered questions which will provide new insights into this exciting and evolving disease entity. D. Joshi and G. J. M. Webster Copyright © 2014 D. Joshi and G. J. M. Webster. All rights reserved. Ribavirin at the Era of Novel Direct Antiviral Agents for the Treatment of Hepatitis C Virus Infection: Relevance of Pharmacological Monitoring Tue, 30 Sep 2014 13:53:30 +0000 Ribavirin is often used for the treatment of hepatitis C virus (HCV) infection. Although its mechanisms of action remain to be clearly elucidated, ribavirin plays a beneficial role for achieving virological response and decreasing the rate of virological relapse after treatment cessation. However, ribavirin may induce side effects leading to early treatment discontinuation. Among them, hemolytic anemia is the most frequent and results from intraerythrocyte accumulation. Pharmacological studies have shown that early ribavirin exposure assessed by the area under the curve (AUC) at day 0 and ribavirin trough concentration during the first three months of therapy were correlated with sustained virological response (SVR). These studies highlighted the relevance of ribavirin pharmacologic monitoring and early dose adaptation during therapy. Although the role of ribavirin within new direct acting antiviral (DAA) combinations will probably decrease in the future, its potential benefit in difficult-to-treat patients such as patients with severe hepatopathy or patients who failed triple therapy including patients with multiresistance will need to be further investigated. Pierre Pradat, Victor Virlogeux, Marie-Claude Gagnieu, Fabien Zoulim, and François Bailly Copyright © 2014 Pierre Pradat et al. All rights reserved. Newly Identified Mechanisms of Total Parenteral Nutrition Related Liver Injury Wed, 25 Jun 2014 07:08:40 +0000 Total parenteral nutrition (TPN), a lifesaving therapy, involves providing nutrition by bypassing the gut. Unfortunately it is associated with significant complications including gut atrophy and parenteral nutrition associated liver disease (PNALD). PNALD includes steatosis, cholestasis, disrupted glucose metabolism, disrupted lipid metabolism, cirrhosis, and liver failure. The etiopathogenesis remains poorly defined; however, an altered enterohepatic circulation, disrupting nuclear receptor signaling, is emerging as a promising mechanism. Rodent models and our piglet TPN model have shown that, during regular feeding, bile acids activate farnesoid X receptor (FXR) in the gut and enhance fibroblast growth factor 19 (FGF19) level. FGF19 regulates bile acid, lipid, and glucose metabolism. We noted reduced FGF19 with TPN use and substantial improvement in FGF19, bilirubin, and metabolic profiles with the FXR agonist chenodeoxycholic acid (CDCA). Additionally, CDCA caused gut growth and enhanced expression of glucagon like peptides (GLPs). GLPs regulate gut trophic effects, insulin, glucose homeostasis, and hepatic steatosis. GLP secretion is regulated by the CDCA activated receptor TGR5. This leads to an important conclusion that, in addition to a disrupted FXR-FGF19 axis, a disrupted TGR5-GLP axis may contribute to TPN related pathologies. Thus modulators of FXR-FGF19 and the TGR5-GLP axis could help bring forward novel treatment strategies. Ajay Kumar Jain and Jeffrey H. Teckman Copyright © 2014 Ajay Kumar Jain and Jeffrey H. Teckman. All rights reserved. Cholangiocarcinomas: New Insights from the Discovery of Stem Cell Niches in Peribiliary Glands of the Biliary Tree Thu, 24 Apr 2014 06:12:38 +0000 Peribiliary glands (PBGs) are located in the large intrahepatic and extrahepatic bile ducts. Although they were described many years ago, their functions have been elucidated only in the last couple of years when our group demonstrated that PBGs are niches of multipotent stem/progenitor cells of endodermal origin. These cells express genes of multipotency and can be rapidly differentiated in vitro into hepatocytes, cholangiocytes, and endocrine pancreatic cells. PBGs share common features, in terms of stem/progenitor cell niches, with pancreatic duct glands and colon crypts, glandular structures representing in the adult life the endodermal remnants of fetal life. PBG stem/progenitor cells participate in the renewal of surface biliary epithelium and are active players in chronic pathologies of the biliary tree as well as in cholangiocarcinomas (CCA). Specifically, a large amount of recent evidence indicates that the pure mucin-CCA originates from PBGs; this could explain the similarities with pancreatic ductal adenocarcinoma and colorectal cancer, which also originate from transformed gland cells. In this paper, we summarized our recent findings concerning structure and functions of PBGs with the implications for liver pathophysiology and, specifically, for cancers of the biliary tree. Vincenzo Cardinale, Maria Consiglia Bragazzi, Guido Carpino, Alessia Torrice, Yunfang Wang, Lola McAdams Reid, Eugenio Gaudio, and Domenico Alvaro Copyright © 2014 Vincenzo Cardinale et al. All rights reserved. Noninvasive Biomarkers of Liver Fibrosis: An Overview Tue, 15 Apr 2014 09:03:10 +0000 Chronic liver diseases of differing etiologies are among the leading causes of mortality and morbidity worldwide. Establishing accurate staging of liver disease is very important for enabling both therapeutic decisions and prognostic evaluations. A liver biopsy is considered the gold standard for assessing the stage of hepatic fibrosis, but it has many limitations. During the last decade, several noninvasive markers for assessing the stage of hepatic fibrosis have been developed. Some have been well validated and are comparable to liver biopsy. This paper will focus on the various noninvasive biochemical markers used to stage liver fibrosis. Hind I. Fallatah Copyright © 2014 Hind I. Fallatah. All rights reserved. Targeting Hepatic Glycerolipid Synthesis and Turnover to Treat Fatty Liver Disease Thu, 10 Apr 2014 11:07:01 +0000 Nonalcoholic fatty liver disease (NAFLD) encompasses a spectrum of metabolic abnormalities ranging from simple hepatic steatosis (accumulation of neutral lipid) to development of steatotic lesions, steatohepatitis, and cirrhosis. NAFLD is extremely prevalent in obese individuals and with the epidemic of obesity; nonalcoholic steatohepatitis (NASH) has become the most common cause of liver disease in the developed world. NASH is rapidly emerging as a prominent cause of liver failure and transplantation. Moreover, hepatic steatosis is tightly linked to risk of developing insulin resistance, diabetes, and cardiovascular disease. Abnormalities in hepatic lipid metabolism are part and parcel of the development of NAFLD and human genetic studies and work conducted in experimentally tractable systems have identified a number of enzymes involved in fat synthesis and degradation that are linked to NAFLD susceptibility as well as progression to NASH. The goal of this review is to summarize the current state of our knowledge on these pathways and focus on how they contribute to etiology of NAFLD and related metabolic diseases. George G. Schweitzer and Brian N. Finck Copyright © 2014 George G. Schweitzer and Brian N. Finck. All rights reserved.