L. Grande

Serum leptin levels correlate with hepatic steatosis in chronic hepatitis C

OBJECTIVES:Hepatic steatosis (HS) has been related to obesity and fibrosis in chronic hepatitis C (CHC). The aim of this study was to determine the role of leptin system in HS development.METHODS:Patients (n = 131) with biopsy-proven CHC, positive HCV RNA, and raised ALT were enrolled. Body mass index, percentage of body fat by skin fold measurement, and bioelectrical impedance analysis was calculated and serum leptin concentration measured. Intrahepatic HCV RNA, HS, necroinflammatory activity, and fibrosis were determined in liver biopsy tissue.RESULTS:HS was present in 63 patients (48.1%). Steatosis was evident in 32 of 91 patients (35.2%) infected with genotype 1 and in 22 of 27 patients (81.5%) with genotype 3a (p < 0.001). In patients infected by genotype 3a, HS correlated significantly with intrahepatic HCV RNA load (r= 0.78; p < 0.001). However, in genotype 1, HS was associated with host factors such as leptin, body mass index, percentage of body fat, and visceral obesity. Multivariate analysis showed genotype (OR = 11.54, 95% CI = 1.13–117.14, p = 0.038), leptin levels (OR = 1.09, 95% CI = 1.03–1.17, p = 0.008) and fibrosis (OR = 9.86, 95% CI = 2.11–5.86, p = 0.03) as independent variables of HS development.CONCLUSIONS:Hepatic steatosis was related to genotype, fibrosis degree, and serum leptin levels. Genotype 3 seems to have a viral specific steatogenic effect. Leptin seems to be a link between obesity and steatosis development in CHC genotype 1–infected patients.

Prognostic value of altered oral glutamine challenge in patients with minimal hepatic encephalopathy.

Oral glutamine challenge (OGC) has been found to be safe, and an altered response predicts elevated risk of overt hepatic encephalopathy (HE) in patients with minimal hepatic encephalopathy (MHE). We assessed the survival prognosis of patients with cirrhosis, but without current overt HE, who have an altered OGC and MHE. MHE was inferred using 3 neuropsychological tests. Venous ammonia concentrations were measured pre‐ and post‐60 minutes of a 10 g oral glutamine load. The median follow‐up was 25.2 months, by which time 22 patients had had bouts of overt HE and 18 had died from liver‐related causes. The results in 126 patients with cirrhosis, indicated 25 with MHE and abnormal OGC response. Survival among patients who developed overt HE was 59% at 1 year and 38% at 3 years. In patients without HE, survival was 96% and 86% at 1 and 3 years, respectively (log‐rank 50.9, P < .0001). The presence of MHE was not related to survival (log‐rank 2.21, P = .23). Patients with MHE and abnormal OGC test had elevated mortality risk (log‐rank 13.1, P = .0003). Multivariate analyses indicated Child‐Pugh score (hazard ratio [HR] 1.46; 95% CI, 1.46‐2.08), and MHE plus altered OGC response (HR 5.5; 95% CI, 1.81‐16.6) were predictors of mortality, whether from liver‐related or non–liver‐related causes. In conclusion, a pathological OGC response in patients with MHE appears to be associated with lower survival rate and may prove useful in the selection of candidates for liver transplantation. (HEPATOLOGY 2004;39:939–943.)

Variations in the Promoter Region of the Glutaminase Gene and the Development of Hepatic Encephalopathy in Patients With Cirrhosis: A Cohort Study

BACKGROUND Hepatic encephalopathy is a major complication of cirrhosis and is associated with a poor prognosis. OBJECTIVE To identify mutations in the gene sequence for glutaminase in humans that could be responsible for the development of hepatic encephalopathy in patients with cirrhosis. DESIGN Cohort study. SETTING Outpatient clinics in 6 Spanish hospitals. PATIENTS 109 consecutive patients with cirrhosis in the estimation cohort, 177 patients in the validation cohort, and 107 healthy control participants. MEASUREMENTS Patients were followed every 3 or 6 months until the development of hepatic encephalopathy or liver transplantation, death, or the end of the study. RESULTS The genetic analyses showed that glutaminase TACC and CACC haplotypes were linked to the risk for overt hepatic encephalopathy. Mutation scanning of the glutaminase gene identified a section in the promoter region where base pairs were repeated (a microsatellite). Over a mean follow-up of 29.6 months, hepatic encephalopathy occurred in 28 patients (25.7%) in the estimation cohort. Multivariable Cox models were used to determine the following independent predictors: Child-Turcotte-Pugh stage (hazard ratio [HR], 1.6 [95% CI, 1.29 to 1.98]; P = 0.001), minimal hepatic encephalopathy (HR, 3.17 [CI, 1.42 to 7.09]; P = 0.006), and having 2 long alleles of the microsatellite (HR, 3.12 [CI, 1.39 to 7.02]; P = 0.006). The association between 2 long alleles of the microsatellite and overt hepatic encephalopathy was confirmed in a validation cohort (HR, 2.1 [CI, 1.17 to 3.79]; P = 0.012). Functional studies showed higher luciferase activity in cells transfected with the long form of the microsatellite, which suggests that the long microsatellite enhances glutaminase transcriptional activity. LIMITATION Other genes and allelic variants might be involved in the clinical expression of hepatic encephalopathy. CONCLUSION This study identifies a genetic factor that is associated with development of hepatic encephalopathy in patients with cirrhosis. PRIMARY FUNDING SOURCE Instituto de Salud Carlos III, Spanish Ministry of Health.

Altered response to oral glutamine challenge as prognostic factor for overt episodes in patients with minimal hepatic encephalopathy

BACKGROUND/AIMS We assessed the usefulness of oral glutamine challenge (OGC) and minimal hepatic encephalopathy in evaluating risk of overt hepatic encephalopathy in cirrhotic patients. METHODS Minimal hepatic encephalopathy (MHE) was inferred using neuro-psychological tests. Venous ammonia concentrations were measured pre- and post-60 min (NH(3)-60m) of a 10 g oral glutamine load. Receiver-operating-characteristic curve analysis indicated a pathological glutamine tolerance cut-off value of NH(3)-60m >128 microg/dl. RESULTS In healthy control subjects (n=10) ammonia concentrations remained unchanged but increased significantly in cirrhotic patients (from 70.41+/-45.2 to 127.43+/-78.6; P<0.001). In multiple logistic regression analysis, altered OGC was related to Child-Pugh (odds ratio, OR=7.69; 95% confidence interval, CI=1.72-33.3; P<0.01) and MHE (OR=5.45; 95% CI=1.17-25.4; P<0.05). In the follow-up 11 patients (15%) developed overt hepatic encephalopathy (HE). In multivariate analysis OGC (OR=14.5; 95% CI=1.26-126.3) and MHE (OR=1.56; 95% CI=1.02-21.9) were independently related with HE in the follow-up. Patients with MHE and altered OGC showed significantly higher risk of overt HE in the follow-up (60%) than patients without MHE and normal OGC (2.8%) (Log rank test=21.60; P<0.0001). CONCLUSIONS A pathological OGC in patients with MHE appears to be a prognostic factor for the development of overt hepatic encephalopathy, whereas a normal OGC in patients without MHE could exclude risk of overt HE.

Intrahepatic hepatitis C virus replication is increased in patients with regular alcohol consumption

AIMS To assess clinical significance of liver hepatitis C virus RNA levels and their relationship with epidemiological, biochemical and histological factors. METHODS A total of 50 patients (mean age 35.5+/-7 years) with biopsy-proven chronic hepatitis C infection were recruited. Risk factors were drug abuse (n=21), transfusion (n=16), other parental routes (n=8; surgery=3, tattooing=5), and idiopathic (n=5). Duration of infection was 16+/-9 years. All patients showed abnormal alanine aminotransferase levels and positive serum hepatitis C virus RNA. Hepatitis C virus genotype was assessed by Inno-Lipa. Liver biopsy was performed for histology and for hepatitis C virus RNA quantification by Amplicor-HCV-Monitor Daily alcohol consumption was recorded on two occasions by anamnesis. Inflammation grade was mild (n=31) or severe (n=19). Fibrosis was early stage (n=42) or advanced (n=8). RESULTS Mean hepatitis C virus RNA levels were 9.4x10(5)+/-1.5x10(6) copies/microg of total RNA in liver tissue, and 9.1x10(5)+/-1.3x10(6) copies/ml in serum. Viral load in liver was positively correlated with that in serum (r=0.51, p<0.001) and there was a significant relationship between daily alcohol consumption and intrahepatic hepatitis C virus burden (r=0.53; p<0.001). Patients infected with genotype 3a showed lower intrahepatic hepatitis C virus load than patients infected with genotype 1b; albeit without reaching statistical significance (0.49x10(6)+/-0.89x10(6) vs 1.44x10(6)+/-1.9x10(6) copies/microg of total RNA; p=NS). No relationships were observed between liver viral burden and age, risk factor status, duration of infection, ferritin and alanine aminotransferase levels or with grading and staging. CONCLUSIONS Hepatitis C virus load in serum is a mirror of intrahepatic hepatitis C virus levels. Chronic alcohol consumption enhances intrahepatic hepatitis C virus concentration.

Antiphospholipid antibodies are related to portal vein thrombosis in patients with liver cirrhosis.

The pathogenesis of portal vein thrombosis (PVT) in cirrhotic liver patients is not known. PVT has been related to liver dysfunction, neoplasm, hemodynamic factors, and hypercoagulability states. PVT has been reported in patients with antiphospholipid syndrome without liver cirrhosis. Our aim was to find the role of antiphospholipid antibodies (APAs) and coagulation inhibitors in PVT in patients with liver cirrhosis. We present a case-controlled study, matched by age, liver function, and etiology, to discover the role of APAs and anticoagulant protein activity in PVT in cirrhotic patients. We studied 30 cirrhotic patients: 6 of 10 (60%) patients with PVT were APA-positive, whereas only 2 of 20 (10%) in the cirrhotic control group were APA-positive (p < 0.005). Low serum levels of protein C, protein S antithrombin III, and plasminogen were found in cirrhotic patients; and, no differences were found between patients with and without PVT. Significantly lower protein S and antithrombin III levels were found in patients with Child-Pugh class C. Therefore, APAs were related to PVT in cirrhotic patients; but, a lower concentration of coagulation inhibitors was associated with liver dysfunction alone.

Role of inflammatory response in liver diseases: Therapeutic strategies

Inflammation and tumorigenesis are tightly linked pathways impacting cancer development. Inflammasomes are key signalling platforms that detect pathogenic microorganisms, including hepatitis C virus (HCV) infection, and sterile stressors (oxidative stress, insulin resistance, lipotoxicity) able to activate pro-inflammatory cytokines interleukin-1β and IL-18. Most of the inflammasome complexes that have been described to date contain a NOD-like receptor sensor molecule. Redox state and autophagy can regulate inflammasome complex and, depending on the conditions, can be either pro- or anti-apoptotic. Acute and chronic liver diseases are cytokine-driven diseases as several proinflammatory cytokines (IL-1α, IL-1β, tumor necrosis factor-alpha, and IL-6) are critically involved in inflammation, steatosis, fibrosis, and cancer development. NLRP3 inflammasome gain of function aggravates liver disease, resulting in severe liver fibrosis and highlighting this pathway in the pathogenesis of non-alcoholic fatty liver disease. On the other hand, HCV infection is the primary catalyst for progressive liver disease and development of liver cancer. It is well established that HCV-induced IL-1β production by hepatic macrophages plays a critical and central process that promotes liver inflammation and disease. In this review, we aim to clarify the role of the inflammasome in the aggravation of liver disease, and how selective blockade of this main pathway may be a useful strategy to delay fibrosis progression in liver diseases.

Insulin resistance impairs viral dynamics independently of ethnicity or genotypes.

Background and Aim: Data concerning the influence of insulin resistance (IR) and ethnicity on early phases of viral kinetics after initiation of peginterferon plus ribavirin in treatment-naive, chronic hepatitis C (CHC) patients are limited. Methods: A total of 263 nondiabetic CHC patients treated with peginterferon plus ribavirin were enrolled for analysis from an Egyptian and Spanish center. IR was evaluated by homeostasis model assessment (HOMA)-IR. Hepatitis C virus (HCV) RNA levels were measured at baseline, 48 hours, 2, 4, and 12 weeks after treatment initiation. Sustained virological response (SVR) was examined 24 weeks after therapy discontinuation. Results: Baseline HOMA-IR strongly influenced 48 hours viral dynamics. HCV-RNA decay observed at 48 hours after the first injection of peginterferon was significantly lower (0.91±0.51 log) in patients with HOMA ≥2 compared with those with HOMA <2 (1.8±0.95 log, P=0.005) this effect was independent of stage of liver fibrosis, HCV genotype, and ethnicity. These differences remained with several cutoffs such as HOMA >3 or HOMA >4. Multivariate analysis identified baseline insulin levels as the main independent variable affecting the 48-hour response in addition to baseline HCV-RNA. The difference in early viral kinetics between patients with HOMA ≥2 or <2 is associated with a significant difference in the percentage of patients achieving both rapid virological response and SVR. Conclusions: IR is a major determinant of the early viral kinetic response to peginterferon plus ribavirin, which has a great impact on subsequent rapid virological response and SVR in CHC patients. This suggests that strategies to improve IR may have a positive effect on SVR and may be early monitored.

Colitis ulcerosa grave, con megacolon tóxico, resuelta con infliximab

Infliximab, anticuerpo contra el factor de necrosis tumoral, está actualmente indicado en el tratamiento de la colitis ulcerosa grave, sin respuesta a esteroides, siendo una alternativa al tratamiento más consolidado con ciclosporina (1,2). Hemos asistido recientemente a un paciente con colitis ulcerosa grave y megacolon tóxico con excelente respuesta al tratamiento con infliximab, evitándose la práctica de colectomía.

Genetic and Epigenetic Regulation in Nonalcoholic Fatty Liver Disease (NAFLD)

Genetics and epigenetics play a key role in the development of several diseases, including nonalcoholic fatty liver disease (NAFLD). Family studies demonstrate that first degree relatives of patients with NAFLD are at a much higher risk of the disease than the general population. The development of the Genome Wide Association Study (GWAS) technology has allowed the identification of numerous genetic polymorphisms involved in the evolution of diseases (e.g., PNPLA3, MBOAT7). On the other hand, epigenetic changes interact with inherited risk factors to determine an individual’s susceptibility to NAFLD. Modifications of the histones amino-terminal ends are key factors in the maintenance of chromatin structure and gene expression (cAMP-responsive element binding protein H (CREBH) or SIRT1). Activation of SIRT1 showed potential against the physiological mechanisms related to NAFLD. Abnormal DNA methylation represents a starting point for cancer development in NAFLD patients. Besides, the evaluation of circulating miRNA profiles represents a promising approach to assess and non-invasively monitor liver disease severity. To date, there is no approved pharmacologic therapy for NAFLD and the current treatment remains weight loss with lifestyle modification and exercise. In this review, the status of research into relevant genetic and epigenetic modifiers of NAFLD progression will be discussed.