Vincenzo O. Palmieri

Genome-wide meta-analyses identify three loci associated with primary biliary cirrhosis

A genome-wide association screen for primary biliary cirrhosis risk alleles was performed in an Italian cohort. The results from the Italian cohort replicated IL12A and IL12RB associations, and a combined meta-analysis using a Canadian dataset identified newly associated loci at SPIB (P = 7.9 × 10−11, odds ratio (OR) = 1.46), IRF5-TNPO3 (P = 2.8 × 10−10, OR = 1.63) and 17q12-21 (P = 1.7 × 10−10, OR = 1.38).

Ribavirin-induced anemia: mechanisms, risk factors and related targets for future research.

Ribavirin (RBV) is an antiviral nucleoside analogue commonly used in combination with interferon for the treatment of chronic hepatitis C. Severe anemia develops in about 10% of treated patients, and requires close monitoring of hemoglobin and often RBV dose reduction, which may compromise sustained virologic response. Anemia is likely related to extensive RBV accumulation in erythrocytes subsequent to active unidirectional transmembraneous transport. RBV exerts its toxicity through an inhibition of intracellular energy metabolism and oxidative membrane damage, leading to an accelerated extravascular hemolysis by the reticulo-endothelial system. Concentration-dependent toxicity and improvement of anemia upon dose-reduction point towards the importance of pharmacokinetic factors for RBV-induced anemia. On the other hand, pronounced variability in the correlation between RBV concentration and Hb reduction limits the prediction of anemia based on plasma or erythrocyte concentrations in individual patients and points towards additional factors determining individual susceptibility to RBV-induced anemia. Recent studies suggest that erythrocyte oxidative defense mechanisms may play an important role in RBV-induced anemia. Clinical risk factors for severe RBV-induced anemia include impaired renal function, high age, high dose per body weight and female gender. Determination of RBV concentrations has little value in the management of anemia. The only proven effective prevention of RBV-induced anemia is the concomitant administration of erythropoietin. Future research on RBV pharmacokinetics and pharmacodynamics, as well as erythrocyte antioxidant defense mechanisms may improve safety and efficacy of RBV therapy and guide the development of new treatments for RBV-induced anemia and alternative antiviral agents.

Acute ethanol administration induces oxidative changes in rat pancreatic tissue.

BACKGROUND--There is mounting clinical evidence that ethanol toxicity to the pancreas is linked with glutathione depletion from oxidative stress but there is not experimental proof that this occurs. AIMS AND METHODS--The effect of acute ethanol ingestion (4 g/kg) on the pancreatic content of reduced (GSH) and oxidised (GSSG) glutathione, malondialdehyde (MDA), and carbonyl proteins were therefore studied in the rat. RESULTS--Ethanol caused a significant reduction in GSH (p < 0.02) and an increase in GSSG (p < 0.005), MDA (p < 0.05), and carbonyl proteins (p < 0.05) in the rat pancreas. The GSH/GSSG ratios were significantly decreased after ethanol, especially in rats pretreated with diethylmaleate (DEM), a GSH blocker. Administration of ethanol after DEM further increased the rate of lipid and protein oxidation. Pretreatment with cyanamide (an inhibitor of aldehyde dehydrogenase) but not with 4-methylpyrazole (an alcohol dehydrogenase inhibitor) caused higher production of GSSG and MDA. CONCLUSIONS--These findings indicate that acute ethanol reduces the pancreatic content of GSH, which seems to be protective against ethanol toxicity, since its depletion is accompanied by increased oxidative damage to cell structures. The further increase of lipid peroxidation and GSSG production in the presence of cyanamide suggests that acetaldehyde might be responsible for the oxidative changes that occur in pancreatic cells after ethanol administration.

Gallbladder motor function in gallstone patients: sonographic and in vitro studies on the role of gallstones, smooth muscle function and gallbladder wall inflammation

Gallbladder motility was studied by ultrasound in 100 healthy adult volunteers and 150 gallstone patients, in a subgroup of whom gallstone burden, type and number, gallbladder histology and tensiometric responses of gallbladder strips to cholecystokinin octapeptide were evaluated. Patients were divided into contractors (n = 108) and hypocontractors (n = 42), according to their gallbladder motility pattern in vivo. Contractors showed slower gallbladder emptying and increased fasting and postprandial residual volumes, although the ejected amount of bile was greater than that of controls (20.2 +/- SEM 1.1 vs 16.0 +/- 0.7 ml; p < 0.001). In contrast, hypocontractors exhibited slower and less complete gallbladder emptying than controls with a reduction in the absolute amount of ejected bile. Although gallbladder wall inflammation was mild and comparable in specimens from both groups of patients, the thickness of the muscular layer was greater in hypocontractors than in contractors (1073 +/- 76 vs 745 +/- 75 microns, p < 0.01) and related inversely to postprandial ejected volume (r = -0.42; p < 0.03; n = 32) but positively to gallstone volume (r = 0.40; p < 0.03; n = 32). Compared to contractors, gall-bladder muscle strips of hypocontractors exhibited a decrease in frequency and amplitude of spontaneous contraction and in maximal stress and receptor sensitivity to cholecystokinin octapeptide (0.1 nM-1 microM). Postprandial gallbladder evaculation was unaffected by stone number, and by the presence or absence of stone calcification. Gallstone volume was larger in hypocontractors (19.4 +/- 3.0 ml vs 9.6 +/- 0.9 ml, p < 0.001) than contractors. The comparison of in vitro contractility patterns between cholesterol, mixed and pigment stone patients showed a more severe defect in patients with cholesterol and mixed stones than in those with pigment calculi. In conclusion, in gallstone patients: (i) gallbladder motor dysfunction manifests mainly with increased fasting and postprandial residual volumes in contractors and with markedly increased postprandial residual volumes and decreased gallbladder emptying in hypocontractors; (ii) gallbladder kinetics seem to be influenced by stone volume and cholesterol content of calculi but not stone number, calcification or mild chronic cholecystitis; (iii) a form of hypertrophic leiomyopathy is observed in gallstone patients with the most impaired gallbladder motor function.

Liver breath tests non-invasively predict higher stages of non-alcoholic steatohepatitis

Effectively assessing subtle hepatic metabolic functions by novel non-invasive tests might be of clinical utility in scoring NAFLD (non-alcoholic fatty liver disease) and in identifying altered metabolic pathways. The present study was conducted on 39 (20 lean and 19 obese) hypertransaminasemic patients with histologically proven NAFLD {ranging from simple steatosis to severe steatohepatitis [NASH (non-alcoholic steatohepatitis)] and fibrosis} and 28 (20 lean and eight overweight) healthy controls, who underwent stable isotope breath testing ([(13)C]methacetin and [(13)C]ketoisocaproate) for microsomal and mitochondrial liver function in relation to histology, serum hyaluronate, as a marker of liver fibrosis, and body size. Compared with healthy subjects and patients with simple steatosis, NASH patients had enhanced methacetin demethylation (P=0.001), but decreased (P=0.001) and delayed (P=0.006) ketoisocaproate decarboxylation, which was inversely related (P=0.001) to the degree of histological fibrosis (r=-0.701), serum hyaluronate (r=-0.644) and body size (r=-0.485). Ketoisocaproate decarboxylation was impaired further in obese patients with NASH, but not in patients with simple steatosis and in overweight controls. NASH and insulin resistance were independently associated with an abnormal ketoisocaproate breath test (P=0.001). The cut-off value of 9.6% cumulative expired (13)CO(2) for ketoisocaproate at 60 min was associated with the highest prediction (positive predictive value, 0.90; negative predictive value, 0.73) for NASH, yielding an overall sensitivity of 68% and specificity of 94%. In conclusion, both microsomal and mitochondrial functions are disturbed in NASH. Therefore stable isotope breath tests may usefully contribute to a better and non-invasive characterization of patients with NAFLD.

Effect of dietary restriction and N-acetylcysteine supplementation on intestinal mucosa and liver mitochondrial redox status and function in aged rats.

The age-related changes of glutathione (GSH) levels and the effect of hypocaloric regimen and N-acetylcysteine (NAC) supplementation were investigated in intestinal mucosa and liver mitochondria of 28 months rats. Old rats exhibited lower proteins, GSH and protein sulphydrils (PSH) concentrations, higher GSH-peroxidase (GSH-Px) activity and protein carbonyl deposit, partial inhibition of succinate stimulated mitochondrial state III respiration and decreased mitochondrial nitrosothiols (RSNO) concentration. Lower electric potential and current intensity were found in the colonic mucosa. Old rats undergone hypocaloric regimen showed higher intestinal concentrations of GSH, lower oxidized protein accumulation and GSH-Px activity and higher mitochondrial RSNO levels. Mitochondrial state III respiration and intestinal transport were improved. NAC supplementation enhanced GSH and PSH levels in the ileal but not in the colonic mucosa, GSH and RSNO in liver mitochondria, while GSH-Px and protein carbonyls were decreased everywhere. Mitochondrial respiration ameliorated. In conclusion, ageing is characterized by a spread decrease of GSH concentrations, increased protein oxidation and decreased mitochondrial NO content. Hypocaloric diet ameliorated intestinal transport and, as well as NAC, was effective in enhancing GSH levels but at different extent according to the investigated districts. Both interventions reduced the age-associated increase of GSH-Px and protein carbonyls and improved mitochondrial respiration.

Effects of cholestyramine on gallbladder and gastric emptying in obese and lean subjects

Abstract. Gallbladder stasis is frequent in obese subjects and may contribute to their increased risk for gallstone formation. The bile salt sequestrant cholestyramine acutely enhances postprandial gallbladder emptying in lean subjects, through dis‐inhibition of a negative feedback between intraluminal bile salts and CCK release. In this study the effect of cholestyramine on both gallbladder and gastric antrum dynamics were studied by realtime ultrasonography in 12 obese and 15 lean subjects. For the acute study, on different days, subjects ingested a liquid meal (two egg yolks plus water 200 mL, 50 kJ) or a meal with 4g cholestyramine. Gallbladder emptying was impaired in obese patients who had significantly larger fasting gallbladder volume (39.4 ± 6.9 vs. 21.6 ± l.7mL, P<0.02), larger residual volume (12.3 ± 1.8 vs. 4.0 ± 0.5ml, P< 0.0006) and slower emptying time (T/2: 33 ± 2 vs. 21 ± 2 min, P < 0.05) than lean subjects. Integrated antral emptying was also less in obese than lean subjects (5521 ± 578 vs. 7908 ± 491 % 120min‐1, P<0.02). Cholestyramine enhanced postprandial gallbladder emptying in both obese and lean subjects. Gastric emptying was delayed with cholestyramine in lean but not obese subjects. For the chronic study, after 1 month therapy with cholestyramine (4 g every 2 days), the motility tests were repeated in nine obese subjects. Gallbladder and gastric responses to a test meal, with or without cholestyramine, were preserved. We conclude that both gallbladder and antral emptying of a liquid test meal are impaired in obese subjects. Gallbladder emptying improves after acute administration of a low dose cholestyramine with test meal. This effect is sustained after 1 month treatment with a low dose of cholestyramine and does not interfere with gastric emptying of obese patients. Cholestyramine may improve gallbladder hypomotility in obese people.

Non-alcoholic fatty liver disease in the metabolic syndrome

Non-alcoholic fatty liver disease (NAFLD) is often associated with features of the metabolic syndrome, carrying an increased risk to develop non-alcoholic steatohepatitis (NASH), the inflammatory form of liver steatosis. Epidemiological data confirm that obesity, diabetes, hypertension and hyperlipidemia are frequently found in NAFLD and worsen its prognosis because of increased risk of fibrotic evolution, eventually leading to liver cirrhosis. Recent studies confirm the close relationship between the metabolic syndrome and liver steatosis, and further support the detrimental role of oxidative stress and lipid peroxidation, which are pathophysiological processes present in both conditions. Novel diagnostic tools and life style modifications together with targeted therapeutic actions are urgently needed for the management of liver dysfunction in course of metabolic syndrome.

Impaired gallbladder and gastric motility and pathological gastro‐oesophageal reflux in gallstone patients

Impaired gallbladder motility is common in gallstone patients and might be associated with other gastrointestinal defects. Twenty patients with small stones in an opacified gallbladder at oral cholecystography and 20 healthy subjects homogeneous for sex, age and body size were studied by ultrasonography to assess gallbladder and gastric emptying simultaneously in response to a standard liquid meal (120 kcal, 11 g fat, 200 mL). The same subjects underwent ambulatory 24‐h gastro‐oesophageal pH monitoring. Dyspeptic symptoms were specifically investigated using a questionnaire. Gallstone patients had a significantly larger fasting (P < 0.05) and residual (P < 0.005) gallbladder volume with slower (P < 0.05) and less complete (anova, 0.001 < P < 0.05) gastric emptying than healthy control subjects. The speed of antral emptying was significantly correlated with the speed of gallbladder emptying (n = 40, r = + 0.31, P < 0.05). Pathological gastro‐oesophageal reflux was present in 75% and 15% of patients and control subjects respectively (P < 0.05). Overall, 95% of gallstone patients had abnormal pH profiles resulting from pathological gastro‐oesophageal reflux and/or prolonged gastric alkalinization. The speed of post‐prandial antral emptying was significantly correlated with the duration of the longest gastro‐oesophageal reflux episode (r = + 0.30, P < 0.03) and duodeno‐gastric reflux episode (r = + 0.80, P < 0.02). Best predictors for gastric alkalinization were the following indices of gallbladder function: large fasting volume (P = 0.03), large ejection volume (P = 0.009) and slower emptying (P = 0.032). Gallbladder and gastric motility were similar in patients with (n = 12) and without (n = 8) dyspeptic symptoms. Pathological gastro‐oesophageal reflux was found in 83% of dyspeptic patients and in 25% of patients without dyspepsia (P < 0.01). When reflux was present, it was significantly less in asymptomatic than in dyspeptic patients [time at pH < 4, median (range): 6.4% (3.2–22.6%) vs. 47.8% (2.1–87%), P < 0.05]. This study shows that a subgroup of gallstone patients with small—mainly asymptomatic—stones have impaired gallbladder and gastric motility as well as abnormal gastro‐oesophageal pH‐profiles. These findings point to the existence of multiple functional defects of the upper gastrointestinal tract in gallstone disease.

Natural history of malignant bone disease in hepatocellular carcinoma: final results of a multicenter bone metastasis survey.

Background Bone is an uncommon site of metastasis in patients with advanced hepatocellular carcinoma (HCC). Therefore, there are few studies concerning the natural history of bone metastasis in patients with HCC. Patients and Methods Data on clinicopathology, survival, skeletal-related events (SREs), and bone-directed therapies for 211 deceased HCC patients with evidence of bone metastasis were statistically analyzed. Results The median age was 70 years; 172 patients were male (81.5%). The median overall survival was 19 months. The median time to the onset of bone metastasis was 13 months (22.2% at HCC diagnosis); 64.9% patients had multiple bone metastases. Spine was the most common site of bone metastasis (59.7%). Most of these lesions were osteolytic (82.4%); 88.5% of them were treated with zoledronic acid. At multivariate analysis, only the Child Score was significantly correlated with a shorter time to diagnosis of bone metastases (p = 0.001, HR = 1.819). The median survival from bone metastasis was 7 months. At multivariate analysis, HCC etiology (p = 0.005), ECOG performance status (p = 0.002) and treatment with bisphosphonate (p = 0.024) were associated with shorter survival after bone disease occurrence. The site of bone metastasis but not the number of bone lesions was associated with the survival from first skeletal related event (SRE) (p = 0.021) and OS (p = 0.001). Conclusions This study provides a significant improvement in the understanding the natural history of skeletal disease in HCC patients. An early and appropriate management of these patients is dramatically needed in order to avoid subsequent worsening of their quality of life.