Joan Caballería

S-adenosylmethionine in alcoholic liver cirrhosis: a randomized, placebo-controlled, double-blind, multicenter clinical trial.

BACKGROUND/AIM The efficacy of S-adenosylmethionine (AdoMet) in the treatment of liver cell injury has been demonstrated in several experimental models. The aim of this study was to investigate the effects of AdoMet treatment in human alcoholic liver cirrhosis. METHODS A randomized, double-blind trial was performed in 123 patients treated with AdoMet (1200 mg/day, orally) or placebo for 2 years. All patients had alcoholic cirrhosis, and histologic confirmation of the diagnosis was available in 84% of the cases. Seventy-five patients were in Child class A, 40 in class B, and 8 in class C. Sixty-two patients received AdoMet and 61 received placebo. RESULTS At inclusion into the trial no significant differences were observed between the two groups with respect to sex, age, previous episodes of major complications of cirrhosis, Child classification and liver function tests. The overall mortality/liver transplantation at the end of the trial decreased from 30% in the placebo group to 16% in the AdoMet group, although the difference was not statistically significant (p = 0.077). When patients in Child C class were excluded from the analysis, the overall mortality/liver transplantation was significantly greater in the placebo group than in the AdoMet group (29% vs. 12%, p = 0.025), and differences between the two groups in the 2-year survival curves (defined as the time to death or liver transplantation) were also statistically significant (p = 0.046). CONCLUSIONS The present results indicate that long-term treatment with AdoMet may improve survival or delay liver transplantation in patients with alcoholic liver cirrhosis, especially in those with less advanced liver disease.

Histological course of alcoholic hepatitis. Influence of abstinence, sex and extent of hepatic damage.

The factors influencing the histological evolution of alcoholic hepatitis without cirrhosis have been evaluated in 26 patients (14 males and 12 females) submitted to repeated liver biopsies over a mean period of 1.7 years (1-3). Drinking habits during follow-up were checked by inquiries to patients and relatives and by serial determination of ethanol in urine. At the end of the follow-up, 9 patients (34.6%) had progressed to cirrhosis, 5 (19.2%) still had alcoholic hepatitis and 12 (46.1%) had normal liver or only minimal changes. Nine patients continued drinking heavily, 4 reduced their daily intake markedly and 13 stopped drinking. Improvement of liver lesions was observed in 9 of the abstainers and in 3 non-abstainers that had markedly reduced their alcohol consumption. Among the 9 patients with persistent heavy alcohol consumption, 5 developed cirrhosis and 4 still showed alcoholic hepatitis in their last biopsy. Cirrhosis also developed over 1-2 years in 4 females who had stopped drinking, indicating a marked influence of sex on the course of alcoholic hepatitis. Progression of the disease to cirrhosis despite abstinence occurred in a high proportion of women (4/7) but not in men (0/6). These observations indicate that discontinuation of heavy alcohol consumption often results in improvement of liver lesion in patients with alcoholic hepatitis. However, the risk of progression to cirrhosis remains elevated in women.

A New Scoring System for Prognostic Stratification of Patients With Alcoholic Hepatitis

OBJECTIVES: Prognostic stratification of patients with alcoholic hepatitis (AH) may improve the clinical management and facilitate clinical trials. We aimed at developing a scoring system capable of providing prognostic stratification of patients with AH.METHODS: Patients with biopsy-proven AH were prospectively included between 2000 and 2006. The biochemical, clinical, portal hemodynamic and histological parameters were evaluated. A Cox regression model was used for univariate and multivariate analyses. A predictive score was built using variables obtained at admission identified in the multivariate analysis. The resulting score was validated in an independent prospective cohort.RESULTS: In total, 103 patients with biopsy-proven AH were included in the study cohort. Age, serum bilirubin, serum creatinine, and international normalized ratio (INR) independently predicted 90-day mortality. We generated the Age, serum Bilirubin, INR, and serum Creatinine (ABIC) score: (age × 0.1) + (serum bilirubin × 0.08) + (serum creatinine × 0.3) + (INR × 0.8). The area under the curve (AUC) was 0.82. Using the Kaplan-Meier analysis with the cutoff values of 6.71 and 9.0, we identified patients with low, intermediate, and high risk of death at 90 days (100%, 70%, and 25% of survival rate, respectively). Using the same cutoff values, the ABIC score also stratified patients according to their risk of death at 1 yr. These results were validated by a confirmatory cohort (N = 80).CONCLUSIONS: The ABIC score is a new tool that allows the stratification of risk of death in patients with AH at 90 days and 1 yr. This score can help improve the management of these patients and also help to perform clinical trials.

Effects of S-adenosylmethionine on lipid peroxidation and liver fibrogenesis in carbon tetrachloride-induced cirrhosis.

BACKGROUND/AIM The aim of this study was to investigate the effects of S-adenosylmethionine on liver peroxidation and liver fibrogenesis in carbon tetrachloride-induced cirrhosis. METHODS Cirrhosis was induced in three groups of six rats by repeated injections of carbon tetrachloride over 9 weeks. One group of animals was treated only with carbon tetrachloride, and the other two received carbon tetrachloride plus S-adenosylmethionine (10 mg/kg intramuscularly daily) from week 3 to week 9, and from week 6 to week 9 of the study, respectively. Two additional groups of six rats, a control group and a group treated only with S-adenosylmethionine, were also studied. Glutathione concentration, thiobarbituric acid-reactive substances, collagen content, prolyl hydroxylase activity, and procollagen type I mRNA expression were determined in liver samples. RESULTS All carbon tetrachloride-treated rats had cirrhosis at the end of the study. Cirrhosis was also present in five of the six carbon tetrachloride-treated rats receiving S-adenosylmethionine for 3 weeks, but in only one of the six rats that received S-adenosylmethionine for 6 weeks. Hepatic glutathione was significantly diminished in carbon tetrachloride-treated rats (2.7 +/- 0.3 mumol/g tissue) and returned to normal in rats receiving S-adenosylmethionine for 3 or 6 weeks (3.7 +/- 0.13 and 3.9 +/- 0.11 mumol/g tissue, respectively). The hepatic thiobarbituric acid-reactive substances were significantly lower in rats treated with carbon tetrachloride and S-adenosylmethionine for 6 weeks (98 +/- 5 nmol/g) than in rats treated with carbon tetrachloride (134 +/- 12 nmol/g) and in those treated with carbon tetrachloride and S-adenosylmethionine for 3 weeks (127 +/- 13 nmol/g). There were no differences in either hepatic collagen and prolyl hydroxylase activity between rats that received only carbon tetrachloride and those treated with S-adenosylmethionine for 3 weeks. In contrast, carbon tetrachloride-treated rats receiving S-adenosylmethionine for 6 weeks had significantly lower collagen and prolyl hydroxylase activity than the other two groups. A much greater increase in procollagen type I mRNA was found in carbon tetrachloride-treated rats than in rats treated with carbon tetrachloride and S-adenosylmethionine for 6 weeks. Furthermore, there was a significant correlation between the hepatic thiobarbituric acid-reactive substances and prolyl hydroxylase activity and hepatic collagen. CONCLUSIONS We conclude that the early administration of S-adenosylmethionine in a model of carbon tetrachloride-induced liver injury restores glutathione levels and reduces lipid peroxidation, resulting in less advanced liver fibrosis.

Specific contribution of methionine and choline in nutritional nonalcoholic steatohepatitis.Impact on mitochondrial S-adenosyl-L-methionine and glutathione

The pathogenesis and treatment of nonalcoholic steatohepatitis (NASH) are not well established. Feeding a diet deficient in both methionine and choline (MCD) is one of the most common models of NASH, which is characterized by steatosis, mitochondrial dysfunction, hepatocellular injury, oxidative stress, inflammation, and fibrosis. However, the individual contribution of the lack of methionine and choline in liver steatosis, advanced pathology and impact on mitochondrial S-adenosyl-l-methionine (SAM) and glutathione (GSH), known regulators of disease progression, has not been specifically addressed. Here, we examined the regulation of mitochondrial SAM and GSH and signs of disease in mice fed a MCD, methionine-deficient (MD), or choline-deficient (CD) diet. The MD diet reproduced most of the deleterious effects of MCD feeding, including weight loss, hepatocellular injury, oxidative stress, inflammation, and fibrosis, whereas CD feeding was mainly responsible for steatosis, characterized by triglycerides and free fatty acids accumulation. These findings were preceded by MCD- or MD-mediated SAM and GSH depletion in mitochondria due to decreased mitochondrial membrane fluidity associated with a lower phosphatidylcholine/phosphatidylethanolamine ratio. MCD and MD but not CD feeding resulted in increased ceramide levels by acid sphingomyelinase. Moreover, GSH ethyl ester or SAM therapy restored mitochondrial GSH and ameliorated hepatocellular injury in mice fed a MCD or MD diet. Thus, the depletion of SAM and GSH in mitochondria is an early event in the MCD model of NASH, which is determined by the lack of methionine. Moreover, therapy using permeable GSH prodrugs may be of relevance in NASH.

Hereditary hepatic and systemic amyloidosis caused by a new deletion/insertion mutation in the apolipoprotein AI gene.

We report a Spanish family with autosomal-dominant non-neuropathic hereditary amyloidosis with a unique hepatic presentation and death from liver failure, usually by the sixth decade. The disease is caused by a previously unreported deletion/insertion mutation in exon 4 of the apolipoprotein AI (apoAI) gene encoding loss of residues 60-71 of normal mature apoAI and insertion at that position of two new residues, ValThr. Affected individuals are heterozygous for this mutation and have both normal apoAI and variant molecules bearing one extra positive charge, as predicted from the DNA sequence. The amyloid fibrils are composed exclusively of NH2-terminal fragments of the variant, ending mainly at positions corresponding to residues 83 and 92 in the mature wild-type sequence. Amyloid fibrils derived from the other three known amyloidogenic apoAI variants are also composed of similar NH2-terminal fragments. All known amyloidogenic apoAI variants carry one extra positive charge in this region, suggesting that it may be responsible for their enhanced amyloidogenicity. In addition to causing a new phenotype, this is the first deletion mutation to be described in association with hereditary amyloidosis and it significantly extends the value of the apoAI model for investigation of molecular mechanisms of amyloid fibrillogenesis.

Portal hypertension in primary biliary cirrhosis: Relationship with histological features

The prevalence and type of portal hypertension (PH) in primary biliary cirrhosis (PBC) and their relationship with liver lesions have been investigated in 32 patients with the disease. Portal hypertension was considered when oesophageal or gastric varices were observed by endoscopy and/or when hepatic venous pressure gradient measured by hepatic vein catheterization was greater than 6 mmHg. Within 3 days of endoscopy, a liver biopsy was performed for histological staging and semiquantitative grading (0 to 3+) of portal and sinusoidal fibrosis, portal inflammation, piecemeal necrosis, lobular necrosis, cholestasis, as well as the presence of granulomas and Mallorys hyaline. Twenty patients (62.5%) had portal hypertension, five of them showing presinusoidal PH (15.5%) and the remaining 15 (47%) with sinusoidal component. The four patients in stage IV had sinusoidal PH and the only patient in stage I had no PH. The prevalence of portal hypertension was similar in patients in stage II (57%) and stage III (55%), but presinusoidal PH was only observed in patients in stage II. Patients with PH showed significantly higher portal inflammation and piecemeal necrosis than patients without PH. By contrast, there were no differences in portal and sinusoidal fibrosis, nor in the other histologic features. These results indicate that portal hypertension is common in PBC and it may be present in the early stages of the disease. The fact that presinusoidal PH was only observed in patients in stage II suggests that portal hypertension is initially of presinusoidal type, and then as the disease progresses is joined by a sinusoidal component.

The biliary epithelium gives rise to liver progenitor cells

Severe liver diseases are characterized by expansion of liver progenitor cells (LPC), which correlates with disease severity. However, the origin and role of LPC in liver physiology and in hepatic injury remains a contentious topic. We found that ductular reaction cells in human cirrhotic livers express hepatocyte nuclear factor 1 homeobox B (HNF1β). However, HNF1β expression was not present in newly generated epithelial cell adhesion molecule (EpCAM)‐positive hepatocytes. In order to investigate the role of HNF1β‐expressing cells we used a tamoxifen‐inducible Hnf1βCreER/R26RYfp/LacZ mouse to lineage‐trace Hnf1β+ biliary duct cells and to assess their contribution to LPC expansion and hepatocyte generation. Lineage tracing demonstrated no contribution of HNF1β+ cells to hepatocytes during liver homeostasis in healthy mice or after loss of liver mass. After acute acetaminophen or carbon tetrachloride injury no contribution of HNF1β+ cells to hepatocyte was detected. We next assessed the contribution of Hnf1β+‐derived cells following two liver injury models with LPC expansion, a diethoxycarbonyl‐1,4‐dihydro‐collidin (DDC)‐diet and a choline‐deficient ethionine‐supplemented (CDE)‐diet. The contribution of Hnf1β+ cells to liver regeneration was dependent on the liver injury model. While no contribution was observed after DDC‐diet treatment, mice fed with a CDE‐diet showed a small population of hepatocytes derived from Hnf1β+ cells that were expanded to 1.86% of total hepatocytes after injury recovery. Genome‐wide expression profile of Hnf1β+‐derived cells from the DDC and CDE models indicated that no contribution of LPC to hepatocytes was associated with LPC expression of genes related to telomere maintenance, inflammation, and chemokine signaling pathways. Conclusion: HNF1β+ biliary duct cells are the origin of LPC. HNF1β+ cells do not contribute to hepatocyte turnover in the healthy liver, but after certain liver injury, they can differentiate to hepatocytes contributing to liver regeneration. (Hepatology 2014;60:1367–1377)

Cigarette smoking exacerbates nonalcoholic fatty liver disease in obese rats

The prevalence of cigarette smoking (CS) is increased among obese subjects, who are susceptible to develop nonalcoholic fatty liver disease (NAFLD). We investigated the hepatic effects of CS in control and obese rats. Control and obese Zucker rats were divided into smokers and nonsmokers (n = 12 per group). Smoker rats were exposed to 2 cigarettes/day, 5 days/week for 4 weeks. The effects of CS were assessed by biochemical analysis, hepatic histological examination, immunohistochemistry, and gene expression analysis. Phosphorylation of AKT and extracellular signal‐regulated kinase (ERK) and quantification of carbonylated proteins were assessed by western blotting. As expected, obese rats showed hypercholesterolemia, insulin resistance, and histological features of NAFLD. Smoking did not modify the lipidic or glucidic serum profiles. Smoking increased alanine aminotransferase serum levels and the degree of liver injury in obese rats, whereas it only induced minor changes in control rats. Importantly, CS increased the histological severity of NAFLD in obese rats. We also explored the potential mechanisms involved in the deleterious effects of CS. Smoking increased the degree of oxidative stress and hepatocellular apoptosis in obese rats, but not in controls. Similarly, smoking increased the hepatic expression of tissue inhibitor of metalloproteinase‐1 and procollagen‐alpha2(I) in obese rats, but not in controls. Finally, smoking regulated ERK and AKT phosphorylation. The deleterious effects of CS were not observed after a short exposure (5 days). Conclusion: CS causes oxidative stress and worsens the severity of NAFLD in obese rats. Further studies should assess whether this finding also occurs in patients with obesity and NAFLD. (HEPATOLOGY 2010.)

Liver-specific methionine adenosyltransferase MAT1A gene expression is associated with a specific pattern of promoter methylation and histone acetylation: implications for MAT1A silencing during transformation

Methionine adenosyltransferase (MAT) is the enzyme that catalyzes the synthesis of S‐adeno‐sylmethionine (AdoMet), the main donor of methyl groups in the cell. In mammals MAT is the product of two genes, MAT1A and MAT2A. MAT1A is expressed only in the mature liver whereas fetal hepatocytes, extrahepatic tissues and liver cancer cells express MAT2A. The mechanisms behind the tissue and differentiation state specific MAT1A expression are not known. In the present work we examined MAT1A promoter methylation status by means of methylation sensitive restriction enzyme analysis. Our data indicate that MAT1A promoter is hypomethylated in liver and hypermethylated in kidney and fetal rat hepatocytes, indicating that this modification is tissue specific and developmentally regulated. Immunoprecipitation of mononucleosomes from liver and kidney tissues with antibodies mainly specific to acetylated histone H4 and subsequent Southern blot analysis with a MAT1A promoter probe demonstrated that MAT1A expression is linked to elevated levels of chromatin acetylation. Early changes in MAT1A methylation are already observed in the precancerous cirrhotic livers from rats, which show reduced MAT1A expression. Human hepatoma cell lines in which MAT1A is not expressed were also hypermethylated at this locus. Finally we demonstrate that MAT1A expression is reactivated in the human hepatoma cell line HepG2 treated with 5‐aza‐2’‐deoxycytidine or the histone deacetylase inhibitor trichosta‐tin, suggesting a role for DNA hypermethylation and histone deacetylation in MAT1A silencing.—Torres, L., Åvila, M. A., Carretero, M. V., Latasa, M. U., Caballería, J., López‐Rodas, G., Boukaba, A., Lu, S. C., Franco, L., Mato, J. M. Liver‐specific methionine adenosyltransferase MAT1A gene expression is associated with a specific pattern of promoter methylation and histone acetylation: implications for MAT1A silencing during transformation. FASEB J. 14, 95–102(2000)