Liver transplant for cholestatic liver diseases

Challenges in pediatric inherited/metabolic liver disease: Focus on the disease spectrum, diagnosis and management of relatively common disorders

The clinical scenario of pediatric liver disease is becoming more intricate due to changes in the disease spectrum, in which an increasing number of inherited/ metabolic liver diseases are reported, while infectious diseases show a decreasing trend. The similar clinical manifestations caused by inherited/metabolic diseases might be under-recognized or misdiagnosed due to nonspecific characteristics. A delayed visit to a doctor due to a lack of symptoms or mild symptoms at an early stage will result in late diagnosis and treatment. Moreover, limited diagnostic approaches, especially liver biopsy, are not easily accepted by pediatric patients, leading to challenges in etiological diagnosis. Liver dysfunction due to inherited/metabolic diseases is often caused by a variety of metabolites, so precision treatment is difficult; symptomatic treatment is a compelling option for inherited disorders.

Generation of functional ciliated cholangiocytes from human pluripotent stem cells

The derivation of mature functional cholangiocytes from human pluripotent stem cells (hPSCs) provides a model for studying the pathogenesis of cholangiopathies and for developing therapies to treat them. Current differentiation protocols are not efficient and give rise to cholangiocytes that are not fully mature, limiting their therapeutic applications. Here, we generate functional hPSC-derived cholangiocytes that display many characteristics of mature bile duct cells including high levels of cystic fibrosis transmembrane conductance regulator (CFTR) and the presence of primary cilia capable of sensing flow. With this level of maturation, these cholangiocytes are amenable for testing the efficacy of cystic fibrosis drugs and for studying the role of cilia in cholangiocyte development and function. Transplantation studies show that the mature cholangiocytes generate ductal structures in the liver of immunocompromised mice indicating that it may be possible to develop cell-based therapies to restore bile duct function in patients with biliary disease.

The long-term outcomes of deceased-donor liver transplantation for primary biliary cirrhosis: a two-center study in China

Background & Aims

Factors that influence the outcomes after deceased-donor liver transplantation (DDLT) for primary biliary cirrhosis (PBC) are not well known. We aimed to clarify these effects on the outcomes after DDLT.

Methods

We retrospectively analyzed patients with PBC who underwent DDLT from March 2006 to July 2018 at the organ transplantation center of the First Hospital of Jilin University and the First Central Hospital of Tianjin. Changes in liver function were assessed posttransplantation. Recurrence, survival rate, and complications were recorded at follow-up. The effect of liver transplantation on survival and recurrence was evaluated using univariate and/or multivariate Cox regression analyses.

Results

In total, 69 patients with PBC undergoing DDLT were included in this study. At 4 weeks posttransplant, all liver function tests were normal. During a median follow-up time of 32 months, 5-year overall survival and recurrence rates were estimated as 95.1% and 21.8%, respectively. A recipient aspartate aminotransferase-to-platelet ratio index (APRI) greater than 2 was negatively associated with survival (P = 0.0018). Multivariate regression analysis demonstrated that age younger than 48 years was an independent risk factor for recurrent PBC in recipients undergoing liver transplantation (hazard ratio 0.028, 95% confidence interval 0.01-0.71, P = 0.03). Posttransplant infections (62%) and biliary tract complications (26%) were the most common complications.

Conclusion

Liver transplantation is an effective treatment for patients with PBC. Liver function normalizes by 4 weeks posttransplant. Although posttransplant survival rate is high, recurrence is possible. To some extent, survival rate and recurrence rate can be predicted by APRI and age, respectively.

Child with Jaundice and Pruritus: How to Evaluate?

Jaundice with pruritus is a manifestation of cholestasis. The defective biliary drainage causes accumulation of substances that are usually excreted in bile, which in turn causes pruritus. The exact nature of the pruritogen is under evaluation. However, lysophosphatidic acid is the current favourite. The causes of cholestasis can be broadly classified as intra or extrahepatic, with intrahepatic disorders being more often associated with pruritus. Cholestatic phase of acute viral hepatitis, progressive familial intrahepatic cholestasis, syndromic and non-syndromic paucity of intralobular bile ductules, drug induced cholestasis and sclerosing cholangitis (SC) are the common causes in children. An algorithmic approach facilitates early etiological diagnosis by careful clinical evaluation combined with investigations including gamma glutamyl transpeptidase, radiological imaging (ultrasonography, magnetic resonance cholangiopancreatography), liver biopsy and genetic analysis. Management is largely supportive and includes nutritional rehabilitation with supplement of fat soluble vitamins and calcium, stepwise therapy of pruritus with drugs (ursodeoxycholic acid, rifampicin, bile acid sequestrants and/or opioid antagonists) and biliary diversion surgery. Complications of advanced liver disease and portal hypertension need to be addressed. Liver transplantation is required in children with refractory pruritus affecting the quality of life or those with end stage liver disease. Relief of biliary obstruction by endoscopy or surgery and treatment of diseases associated with SC like histiocytosis may be rewarding. Long-term follow-up for development of complications of liver disease and hepatocellular/ cholangiocarcinoma is essential. Thus, an early diagnosis and stepwise treatment with an understanding of the pathogenesis of pruritus in cholestatic disorders may decrease morbidity and mortality.

Primary biliary cirrhosis degree assessment by acoustic radiation force impulse imaging and hepatic fibrosis indicators

AIM: To evaluate the assessment of primary biliary cirrhosis degree by acoustic radiation force impulse imaging (ARFI) and hepatic fibrosis indicators.

METHODS: One hundred and twenty patients who developed liver cirrhosis secondary to primary biliary cirrhosis were selected as the observation group, with the degree of patient liver cirrhosis graded by Child-Pugh (CP) score. Sixty healthy individuals were selected as the control group. The four indicators of hepatic fibrosis were detected in all research objects, including hyaluronic acid (HA), laminin (LN), type III collagen (PC III), and type IV collagen (IV-C). The liver parenchyma hardness value (LS) was then measured by ARFI technique. LS and the four indicators of liver fibrosis (HA, LN, PC III, and IV-C) were observed in different grade CP scores. The diagnostic value of LS and the four indicators of liver fibrosis in determining liver cirrhosis degree with PBC, whether used alone or in combination, were analyzed by receiver operating characteristic (ROC) curve.

RESULTS: LS and the four indicators of liver fibrosis within the three classes (A, B, and C) of CP scores in the observation group were higher than in the control group, with C class > B class > A class; the differences were statistically significant (P < 0.01). Although AUC values of LS within the three classes of CP scores were higher than in the four indicators of liver fibrosis, sensitivity and specificity were unstable. The ROC curves of LS combined with the four indicators of liver fibrosis revealed that: AUC and sensitivity in all indicators combined in the A class of CP score were higher than in LS alone, albeit with slightly decreased specificity; AUC and specificity in all indicators combined in the B class of CP score were higher than in LS alone, with unchanged sensitivity; AUC values (0.967), sensitivity (97.4%), and specificity (90%) of all indicators combined in the C class of CP score were higher than in LS alone (0.936, 92.1%, 83.3%).

CONCLUSION: The diagnostic value of PBC cirrhosis degree in liver cirrhosis degree assessment by ARFI combined with the four indicators of serum liver fibrosis is of satisfactory effectiveness and has important clinical application value.

Liver Transplantation for Cholestatic Liver Diseases in Adults

Liver transplantation (LT) is an established lifesaving therapy for patients with cholestatic liver diseases, including primary cholestatic diseases, namely primary sclerosing cholangitis and primary biliary cirrhosis, as well as secondary forms of cholestatic liver disease, including those with cholestatic complications of LT needing a retransplant. Patients with cholestatic liver diseases can be transplanted for complications of end-stage liver disease or for disease-specific symptoms before the onset of end-stage liver disease. These patients should be regularly assessed. Patient survival after LT for cholestatic liver diseases is generally better than for other indications.

Critical review of resveratrol in xenobiotic-induced hepatotoxicity

Use of natural products is increasingly popular. In fact, many patients with liver diseases self-medicate with herbal supplements. Resveratrol (RSV), in particular, is a common natural product that can reduce injury in experimental models of liver disease. Xenobiotic hepatotoxicity is a particularly important area-of-need for therapeutics. Drug-induced liver injury, for example, is the most common cause of acute liver failure (ALF) and ALF-induced deaths in many countries. Importantly, RSV protects against hepatotoxicity in animal models in vivo caused by several drugs and chemicals and may be an effective intervention. Although many mechanisms have been proposed to explain the protection, not all are consistent with other data. Furthermore, RSV suffers from other issues, including limited bioavailability due to extensive hepatic metabolism. The purpose of this article is to summarize recent findings on the protective effects of RSV in xenobiotic-induced liver injury and other forms of liver injury and to provide a critical review of the underlying mechanisms. New mechanisms that are more consistent with data emerging from the toxicology field are suggested. Efforts to move RSV into clinical use are also considered. Overall, RSV is a promising candidate for therapeutic use, but additional studies are needed to better understand its effects.

Histone deacetylase 4 promotes cholestatic liver injury in the absence of prohibitin-1

Prohibitin-1 (PHB1) is an evolutionarily conserved pleiotropic protein that participates in diverse processes depending on its subcellular localization and interactome. Recent data have indicated a diverse role for PHB1 in the pathogenesis of obesity, cancer, and inflammatory bowel disease, among others. Data presented here suggest that PHB1 is also linked to cholestatic liver disease. Expression of PHB1 is markedly reduced in patients with primary biliary cirrhosis and biliary atresia or with Alagille syndrome, two major pediatric cholestatic conditions. In the experimental model of bile duct ligation, silencing of PHB1 induced liver fibrosis, reduced animal survival, and induced bile duct proliferation. Importantly, the modulatory effect of PHB1 is not dependent on its known mitochondrial function. Also, PHB1 interacts with histone deacetylase 4 (HDAC4) in the presence of bile acids. Hence, PHB1 depletion leads to increased nuclear HDAC4 content and its associated epigenetic changes. Remarkably, HDAC4 silencing and the administration of the HDAC inhibitor parthenolide during obstructive cholestasis in vivo promote genomic reprogramming, leading to regression of the fibrotic phenotype in liver-specific Phb1 knockout mice.

CONCLUSION

PHB1 is an important mediator of cholestatic liver injury that regulates the activity of HDAC4, which controls specific epigenetic markers; these results identify potential novel strategies to treat liver injury and fibrosis, particularly as a consequence of chronic cholestasis.

Functional and structural features of cholangiocytes in health and disease

Cholangiocytes are the epithelial cells that line the bile ducts. Along the biliary tree, two different kinds of cholangiocytes exist; small and large cholangiocytes. Each type has important differences in their biological role in physiological and pathological conditions. In response to injury, cholangiocytes become reactive and acquire a neuroendocrine-like phenotype with the secretion of a number of peptides. These molecules act in an autocrine/paracrine fashion to modulate cholangiocyte biology and determine the evolution of biliary damage. The failure of such mechanisms is believed to influence the progression of cholangiopathies, a group of diseases that selectively target biliary cells. Therefore, the understanding of mechanisms regulating cholangiocyte response to injury is expected to foster the development of new therapeutic options to treat biliary diseases. In the present review, we will discuss the most recent findings in the mechanisms driving cholangiocyte adaptation to damage, with particular emphasis on molecular pathways that are susceptible of therapeutic intervention. Morphogenic pathways (Hippo, Notch, Hedgehog), which have been recently shown to regulate biliary ontogenesis and response to injury, will also be reviewed. In addition, the results of ongoing clinical trials evaluating new drugs for the treatment of cholangiopathies will be discussed.