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In the present study, we examined the effects of cortisol on steatotic and non-steatotic liver grafts from brain-dead donors and characterized the underlying mechanisms involved. Non-steatotic liver grafts showed reduced cortisol and increased cortisone levels in association with up-regulation of enzymes that inactivate cortisol. Conversely, steatotic liver grafts exhibited increased cortisol and reduced cortisone levels. The enzymes involved in cortisol generation were overexpressed, and those involved in cortisol inactivation or clearance were down-regulated in steatotic liver grafts. Exogenous administration of cortisol negatively affected hepatic damage and survival rate in non-steatotic liver transplantation (LT); however, cortisol treatment up-regulated the phosphoinositide 3-kinase (PI3K)–protein kinase C (PKC) pathway, resulting in protection against the deleterious effects of brain-dead donors on damage and inflammatory response in steatotic LT as well as in increased survival of recipients. The present study highlights the differences in the role of cortisol and hepatic mechanisms that regulate cortisol levels based on the type of liver. Our findings suggest that cortisol treatment is a feasible and highly protective strategy to reduce the adverse effects of brain-dead donor livers in order to ultimately improve liver graft quality in the presence of steatosis, whereas cortisol treatment would not be recommended for non-steatotic liver grafts. * 11β-HSD1, : 11 β-hydroxysteroid dehydrogenase type 1; 11β-HSD2, : 11 β-hydroxysteroid dehydrogenase type 2; 5αR1, : 5α-reductase 1 enzyme; 5αR2, : 5α-reductase 2 enzyme; 5βR, : 5β-reductase enzyme; ACTH, : adrenocorticotropin hormone; Akt, : protein kinase B; ALT, : alanine aminotransferase; AST, : aspartate aminotransferase; BD, : brain dead; CRH, : corticotropin-releasing hormone; HPA, : hypothalamus–pituitary–adrenal axis; i.p., : intraperitoneal; I/R, : ischemia-reperfusion; i.v., : intravenous; Ln, : lean; LT, : liver transplantation; MDA, : malondialdehyde; MPO, : myeloperoxidase; Ob, : obese; PI3K, : phosphoinositide 3-kinase; PKC, : protein kinase C; UW, : University of Wisconsin

Background & Aims Most liver grafts undergoing transplantation derive from brain dead donors, which may also show hepatic steatosis, being both characteristic risk factors in liver transplantation. Ischemic preconditioning shows benefits when applied in non-brain dead clinical situations like hepatectomies, whereas it has been less promising in the transplantation from brain dead patients. This study examined how brain death affects preconditioned steatotic and non-steatotic liver grafts undergoing transplantation. Methods Steatotic and non-steatotic grafts from non-brain dead and brain dead-donors were cold stored for 6h and then transplanted. After 2, 4, and 16h of reperfusion, hepatic damage was analysed. In addition, two therapeutic strategies, ischemic preconditioning and/or acetylcholine pre-treatment, and their underlying mechanisms were characterized. Results Preconditioning benefits in non-brain dead donors were associated with nitric oxide and acetylcholine generation. In brain dead donors, preconditioning generated nitric oxide but did not promote acetylcholine upregulation, and this resulted in inflammation and damage. Acetylcholine treatment in brain dead donors, through PKC, increased antioxidants and reduced lipid peroxidation, nitrotyrosines and neutrophil accumulation, altogether protecting against damage. The combination of acetylcholine and preconditioning conferred stronger protection against damage, oxidative stress and neutrophil accumulation than acetylcholine treatment alone. These superior beneficial effects were due to a selective preconditioning-mediated generation of nitric oxide and regulation of PPAR and TLR4 pathways, which were not observed when acetylcholine was administered alone. Conclusions Our findings propose the combination of acetylcholine+preconditioning as a feasible and highly protective strategy to reduce the adverse effects of brain death and to ultimately improve liver graft quality.

Background & Aims This study examined whether the regulation of resistin and visfatin could reduce damage and improve regeneration in both steatotic and non-steatotic livers undergoing partial hepatectomy under ischemia-reperfusion, a procedure commonly applied in clinical practice to reduce bleeding. Methods Resistin and visfatin were pharmacologically modulated in lean and obese animals undergoing partial hepatectomy under ischemia-reperfusion. Results No evident role for these adipocytokines was observed in non-steatotic livers. However, obese animals undergoing liver surgery showed increased resistin in liver and plasma, without changes in adipose tissue, together with visfatin downregulation in liver and increment in plasma and adipose tissue. Endogenous resistin maintains low levels of visfatin in the liver by blocking its hepatic uptake from the circulation, thus regulating the visfatin detrimental effects on hepatic damage and regenerative failure. Indeed, the administration of anti-resistin antibodies increased hepatic accumulation of adipocyte-derived visfatin, exacerbating damage and regenerative failure. Interestingly, treatment with anti-visfatin antibodies protected steatotic livers, and similar results were obtained with the concomitant inhibition of resistin and visfatin. Thus, when visfatin was inhibited, the injurious effects of anti-resistin antibodies disappeared. Herein we show that upregulation of visfatin increased NAD levels in the remnant steatotic liver, whereas visfatin inhibition decreased them. These later observations suggest that visfatin may favour synthesis of NAD instead of DNA and induces alterations in amino acid metabolism-urea cycle and NO production, overall negatively affecting liver viability. Conclusions Our results indicate the clinical potential of visfatin blocking-based therapies in steatotic livers undergoing partial hepatectomy with ischemia-reperfusion.

The intent of this study was to examine the effects of regulating cortisol levels on damage and regeneration in livers with and without steatosis subjected to partial hepatectomy under ischaemia–reperfusion. Ultimately, we found that lean animals undergoing liver resection displayed no changes in cortisol, whereas cortisol levels in plasma, liver and adipose tissue were elevated in obese animals undergoing such surgery. Such elevations were attributed to enzymatic upregulation, ensuring cortisol production, and downregulation of enzymes controlling cortisol clearance. In the absence of steatosis, exogenous cortisol administration boosted circulating cortisol, while inducing clearance of hepatic cortisol, thus maintaining low cortisol levels and preventing related hepatocellular harm. In the presence of steatosis, cortisol administration was marked by a substantial rise in intrahepatic availability, thereby exacerbating tissue damage and regenerative failure. The injurious effects of cortisol were linked to high hepatic acethylcholine levels. Upon administering an α7 nicotinic acethylcholine receptor antagonist, no changes in terms of tissue damage or regenerative lapse were apparent in steatotic livers. However, exposure to an M3 muscarinic acetylcholine receptor antagonist protected livers against damage, enhancing parenchymal regeneration and survival rate. These outcomes for the first time provide new mechanistic insight into surgically altered steatotic livers, underscoring the compelling therapeutic potential of cortisol–acetylcholine–M3 muscarinic receptors.

Numerous steatotic livers are discarded for transplantation because of their poor tolerance of ischemia-reperfusion (I/R). The injurious effects of retinol-binding protein 4 (RBP4) in various pathologies are well documented. RBP4 levels are reduced by peroxisome proliferator-activated receptor-γ (PPARγ) agonists. Strategies aimed at increasing PPARγ protect steatotic livers under warm ischemia. Ischemic preconditioning (PC) based on brief periods of I/R protects steatotic liver grafts against I/R injury, but the responsible mechanism is poorly understood. We examined the roles of RBP4 and PPARγ in I/R injury associated with steatotic liver transplantation and the benefits of PC in such situations. We report that RBP4 and PPARγ expression levels in nonsteatotic livers were similar to those found in the sham group. However, reduced RBP4 and increased PPARγ levels were observed in steatotic livers. Treatment with either RBP4 or a PPARγ antagonist was effective only in steatotic livers. PC, which increased RBP4 levels, and RBP4 treatment both reduced PPARγ levels and hepatic injury in steatotic livers. When PPARγ was activated, neither RBP4 treatment nor PC (despite RBP4 induction) protected steatotic livers. In conclusion, steatotic liver grafts are more predisposed to down-regulate RBP4 and overexpress PPARγ. RBP4 treatment and PC, through RBP4 induction, reduced PPARγ levels in steatotic liver grafts, thus protecting them from the PPARγ detrimental effects.

This study examined the effects of epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I) supplementation to University of Wisconsin solution (UW) in steatotic and nonsteatotic livers during cold storage. Hepatic injury and function were evaluated in livers preserved for 24 hours at 4°C in UW and in UW with EGF and IGF-I (separately or in combination) and then perfused ex vivo for 2 hours at 37°C. AKT was inhibited pharmacologically. In addition, hepatic injury and survival were evaluated in recipients who underwent transplantation with steatotic and nonsteatotic livers preserved for 6 hours in UW and UW with EGF and IGF-I (separately or in combination). The results, based on isolated perfused liver, indicated that the addition of EGF and IGF-I (separately or in combination) to UW reduced hepatic injury and improved function in both liver types. A combination of EGF and IGF-I resulted in hepatic injury and function parameters in both liver types similar to those obtained by EGF and IGF-I separately. EGF increased IGF-I, and both additives up-regulated AKT in both liver types. This was associated with glycogen synthase kinase-3β (GSK3β) inhibition in nonsteatotic livers and PPARγ overexpression in steatotic livers. When AKT was inhibited, the effects of EGF and IGF-I on GSK3β, PPARγ, hepatic injury and function disappeared. The benefits of EGF and IGF-I as additives in UW solution were also clearly seen in the liver transplantation model, because the presence of EGF and IGF-I (separately or in combination) in UW solution reduced hepatic injury and improved survival in recipients who underwent transplantation with steatotic and nonsteatotic liver grafts. In conclusion, EGF and IGF-I may constitute new additives to UW solution in steatotic and nonsteatotic liver preservation, whereas a combination of both seems unnecessary. Liver Transpl 16:1098–1111, 2010. © 2010 AASLD.

Here we examine the effect of adding carvedilol (CVD) to University of Wisconsin (UW) solution on the preservation of steatotic and nonsteatotic livers during cold ischemia and after normothermic reperfusion. We used an isolated perfused rat liver model. The following protocols were evaluated. Protocol 1 concerned the effect of CVD after cold ischemia. Steatotic and nonsteatotic livers were preserved for 24 hours in UW solution alone or with CVD. Livers without cold ischemia were used as controls. Transaminases were evaluated in the flushing effluent. Protocol 2 involved the effect of CVD after reperfusion. Both liver types were preserved for 24 hours in UW solution alone or with CVD and then perfused ex vivo for 2 hours at 37 degrees C. Livers flushed and perfused without ischemia were used as controls. Hepatic injury and functionality [transaminases, bile production, and hepatic clearance of sulfobromophthalein (BSP)] were evaluated after reperfusion. In addition, factors potentially involved in hepatic ischemia-reperfusion injury, including oxidative stress (malondialdehyde and superoxide anion levels), mitochondrial damage (glutamate dehydrogenase activity), microcirculatory disorders (flow rate and vascular resistance), and adenosine triphosphate (ATP) depletion, were evaluated after reperfusion. After cold ischemia, steatotic livers preserved in UW solution showed higher transaminase levels than nonsteatotic livers. After reperfusion, steatotic livers preserved in UW solution showed higher transaminase levels and lower bile production and BSP clearance than nonsteatotic livers. Alterations in the perfusion flow rate and vascular resistance, mitochondrial damage, and reduced ATP content were more evident in steatotic livers preserved in UW solution. The addition of CVD to UW solution reduced hepatic injury, obstructed its mechanisms, and improved hepatic functionality in both liver types. We conclude that CVD is a useful additive for UW solution that improves the preservation of steatotic and nonsteatotic livers subjected to prolonged cold ischemia.

Background/Aims Thinning of the vascular wall occurs in conductance vessels of cirrhotic rats. Increased nitric oxide synthase (NOS) activity has been involved in the pathogenesis of this phenomenon. Therefore, we assessed the NO-regulated cell signaling pathways participating in vascular remodeling in cirrhosis. Methods Aortas were obtained from 15 control and 15 cirrhotic rats. Phosphorylated p38 MAPK and ERK1/2 were used to evaluate the activation of cell MAPK signaling pathways. Extracellular matrix (ECM) turnover was estimated by measuring matrix metalloproteinases (MMPs) activity and protein expression of collagen IV, MMP-2, MMP-9 and tissue inhibitor of MMPs (TIMP)-2. Thereafter, 12 control and 12 cirrhotic rats received N ϖ -nitro-l-arginine-methyl-ester or vehicle daily for 11 weeks. Results Cirrhotic vessels showed a reduction in ERK1/2 phosphorylation, lower MMP activity, decreased MMPs expression and higher collagen IV and TIMP-2 abundance, compared to control rats. Chronic NOS inhibition normalized ERK1/2 phosphorylation and MMPs activity, increased MMPs abundance and decreased TIMP-2 expression in cirrhotic rats. Conclusions Vascular remodeling in cirrhotic rats is mediated by down-regulation of cell growth and impaired ERK1/2 activation and subsequent imbalance of ECM turnover. These results further stress the importance of vascular NO overactivity in the reduction of vascular wall thickness in cirrhosis.

Ascites is the abnormal accumulation of fluid in the peritoneal cavity. The most frequent cause of ascites is portal hypertension related to cirrhosis. Ascites in patients with cirrhosis is the consequence of the homeostatic activation of vasoconstrictor systems and sodium retention. These mechanisms are triggered by a decrease in effective arterial blood volume due to a severe arterial vasodilatation located mainly in the splanchnic circulation. The ascitic fluid of patients with cirrhosis is generally low in proteins and albumin. Since the presence of ascites is associated with poor prognosis and low survival, the patients with ascites should be evaluated for liver transplantation. The treatment consists basically of a negative sodium balance that is obtained by decreasing the sodium intake and increasing its excretion by the administration of diuretic agents. The patients in whom these drugs are not effective or cannot be administered (because they develop adverse effects, a condition well known as refractory ascites), should be treated with large-volume paracentesis plus albumin.

Background/Aims Renal dysfunction is a frequent complication in advanced cirrhosis. The mechanisms underlying this complication have classically been addressed through conventional methods of study of candidate genes, but never on a genome-wide scale. In this investigation, we used microarrays to monitor global gene expression changes in the kidney of cirrhotic rats. Methods Renal samples were obtained from control and carbon tetrachloride-induced cirrhotic rats. RNA samples were reverse-transcribed into Cy5-labeled cDNA, combined with a Cy3-labeled reference and hybridized to oligonucleotide microarrays. Microarrays were scanned in a Genepix 4000B and data analyzed by Luminator v2.0 software. Results A total of 620 genes were differentially regulated (354 up and 266 down) in the cirrhotic kidney, accounting for approximately 11% of all analyzed transcripts. Functional grouping of these genes revealed that 47 were related to the category of vascular tone and 85 to transporters/channels. Among these, we identified genes and pathways already associated with renal dysfunction as well as a new subset of genes previously unknown to participate in this complication, including a G protein-coupled receptor that binds apelin, a protein phosphatase (calcineurin B) and a number of neuropeptide receptors and growth factors. Conclusions These findings furnish new data for mechanistic investigation into renal dysfunction in cirrhosis.

1 A disturbance in body water homeostasis is a common feature in advanced cirrhosis. This disturbance is always associated with the existence of ascites and is characterized by an inability to adjust the amount of water excreted in the urine to the amount of water ingested. Vasopressin (AVP) is of major importance in the pathogenesis of water retention and hyponatremia in cirrhosis. 2 The current study assessed the renal, hormonal and hemodynamic effects induced by 10-day chronic oral administration of RWJ-351647 (0.5 mg kg(-1) daily), a new nonpeptide V(2)-AVP antagonist, in rats with CCl(4)-induced cirrhosis, ascites and severe water retention. Urine volume (UV), urine osmolality and sodium and potassium excretion were measured daily. At the end of the study, systemic hemodynamic parameters were also assessed. 3 Long-term administration of RWJ-351647 has an aquaretic effect in rats with cirrhosis, ascites, water retention and hypo-osmolality. It increases UV (ANOVA: F=7.32, P

Background & Aims: There is a long-standing interest in the identification of endothelial-specific pathways for therapeutic targeting in cirrhosis. Therefore, the aim of this study was to evaluate differences in gene expression patterns between liver endothelial cells (LECs) from control and cirrhotic rats by using microarrays. Methods: LECs were obtained by isopycnic centrifugation. LECs gene expression was then analyzed on high-density oligonucleotide microarrays. Results: Analysis of gene expression revealed that most of the differentially expressed mRNA in cirrhosis are associated with extracellular matrix remodeling, inflammation, antioxidant/stress response, and cell signaling. Conclusions: The collective expression changes observed within some functional groups of genes indicate that LECs in cirrhotic livers may contribute to lymphangiogenesis, enhancement of fibrogenesis and inflammatory processes, changes in cell-cell interaction with up-regulation of adherens junction proteins, and alterations in the intrahepatic vascular tone because of the down-regulation of genes involved in vasodilatation.

Hepatorenal syndrome (HRS) is a major complication of patients with cirrhosis, with the annual incidence in patients with ascites being approximately 8% []. This syndrome develops in the latest phase of the disease and there is now evidence that it is an important determinant of patient survival. Many aspects of HRS are, however, still poorly understood. There are two types of HRS: type 1 or progressive HRS which is associated with a very poor prognosis (median survival rate lower than 2 weeks), and type 2 HRS which is characterized by a steady impairment in circulatory and renal function. The pathogenesis of HRS is a deterioration in effective arterial blood volume due to splanchnic arterial vasodilation and a reduction in venous return and cardiac output. It is therefore not surprising that the syndrome can be reversed by the simultaneous intravenous administration of albumin and arterial vasoconstrictors. Intrarenal mechanisms are also important and require prolonged improvement in circulatory function to be deactivated. Long-term administration of intravenous albumin and vasoconstrictors or the correction of portal hypertension with a transjugular intrahepatic portacaval shunt are effective in the treatment of HRS. They also appear to improve survival and may serve as a bridge to liver transplantation, which is the treatment of choice in these patients.

Important progress has been made recently regarding the pathogenesis and treatment of hepatorenal syndrome (HRS). However, scant information exists about factors predicting outcome in patients with cirrhosis and HRS. Moreover, the prognostic value of the model of end-stage liver disease (MELD) score has not been validated in the setting of HRS. The current study was designed to assess the prognostic factors and outcome of patients with cirrhosis and HRS. The study included 105 consecutive patients with HRS. Forty-one patients had type 1 HRS, while 64 patients had type 2 HRS. Patients with type 1 HRS not only had more severe liver and renal failure than type 2 patients, they also had greater impairment of circulatory function, as indicated by lower arterial pressure and higher activation of vasoconstrictor factors. In the whole series, the median survival was 3.3 months. In a multivariate analysis of survival, only HRS type and MELD score were associated with an independent prognostic value. All patients with type 1 HRS had a high MELD score (> or =20) and showed an extremely poor outcome (median survival: 1 mo). By contrast, the survival of patients with type 2 HRS was longer and dependent on MELD score (> or =20, median survival 3 mo

Background. Hepatitis C recurrence after liver transplantation is often associated with accelerated graft fibrosis and progression to cirrhosis. Because drugs blocking the action of angiotensin-II can reduce fibrosis in different human and experimental models, we assessed the possible beneficial effect of these drugs on graft fibrosis in hepatitis C recurrence after liver transplantation. Methods. We retrospectively reviewed the charts of 128 liver-transplant recipients with hepatitis C recurrence. Twenty-seven patients (group I) received angiotensin converting enzyme inhibitors or angiotensin-II receptor antagonists as antihypertensive treatment, and 101 patients (group II) did not receive these drugs. Results. No significant differences were found between groups I and II in demographic, clinical, and laboratory data. In contrast, cirrhosis in the graft was less frequently observed in group I than in group II during postransplant follow-up: 15% versus 35% (P=0.035), respectively, with a probability of cirrhosis of 9% versus 32% at 5 years after transplantation and 35% versus 70% at 10 years (P=0.0049). Furthermore, the fibrosis stage (scored from 0-4) in the liver biopsy obtained at the end of follow-up was significantly lower in group I than in group II (median [and range]: I [0-4] vs. 2 [0-4]; P=0.038), and the fibrosis progression index (increase of fibrosis stage per year) was also lower in group I than in group II (0.21 [0-0.45] vs. 0.52 [0-2.58]; P=0.006). Conclusion. The administration of angiotensin-blocking agents may be beneficial to reduce the development of graft fibrosis in hepatitis C recurrence after liver transplantation.

Background/Aims Patients with decompensated cirrhosis are prone to develop neutropenia. Although hypersplenism and increased clearance of polymorphonuclear leukocytes (PMN) in the spleen are thought to contribute to neutropenia in these patients, other factors cannot be excluded. The aim of the current study was to investigate whether the presence of increased PMN apoptosis could also contribute to the appearance of neutropenia in these patients. Methods PMN were isolated by Ficoll-Hypaque gradient centrifugation from 17 patients with decompensated cirrhosis (CH group) and 13 patients with compensated chronic liver disease (CT group). PMN were incubated in RPMI 1640 medium at 37 °C in a 5% CO 2 atmosphere and viability and frequency of apoptosis were evaluated after 0, 10, 20 and 40 h of culture. Viability was determined by the MTT assay and apoptosis by microscopic examination of cell morphology (Diff-Quik staining), DNA fragmentation by agarose gel electrophoresis (DNA laddering) and caspase-3 activity by DVDE- p -nitroanilide cleavage. Results Compared to CT patients, PMN isolated from CH patients exhibited a decreased PMN viability and a marked accelerated apoptosis as revealed by an increased number of condensed nuclei, increased DNA laddering and significantly higher caspase-3 activity. Conclusions These findings indicate that shortening of PMN survival via apoptosis may explain in part the neutropenia present in decompensated cirrhotic patients with ascites, thus favoring the development of bacterial infections in these patients.

Previous studies on Spanish patients with Primary Biliary Cirrhosis (PBC) have shown extensive, disease-specific cross-reactivity between the 65-kDa heat shock protein (hsp65) of Mycobacterium gordonae and pyruvate dehydrogenase complex-E2 (PDC-E2), the major target of anti-mitochondrial antibody (AMA). Studies on a British population were unable to substantiate these findings. Having found that there is an excellent and almost unique match between the PDC-E2 autoepitope and a sequence in mycobacterial hsp65s, we tested the corresponding peptides by ELISA for cross-reactivity using sera from 90 PBC patients, 40 Spanish and 50 British, and 84 pathological controls. Reactivity to the MYCGO hsp65(90-104)/human PDC-E2(212-226)pair was present in 19 (47.5%) Spanish PBC patients and in 2 (4%) of the 50 British. Reactivity was not seen in any of the controls. Simultaneous reactivity to mimics was due to cross-reactivity as confirmed by inhibition studies. Three dimensional modelling predicts mycobacterial hsp65(90-104)to be exposed on the surface of the protein. The affinity of anti-hsp65(90-104)antibody was higher than that of anti-PDC-E2(212-226). Hsp65(90-104)is a target of disease-specific cross-reactivity to PDC-E2(212-226). The geographical confinement of this phenomenon is probably the result of complex genetic, environmental and immunological interaction.

Pruritus is a distressing symptom in patients with primary biliary cirrhosis, and when uncontrollable it is an indication for liver transplantation. Since pruritus can result from unknown substances that accumulate systemically as a consequence of impaired biliary secretion, we have assessed whether a new extracorporeal albumin dialysis (ECAD) procedure, the molecular-adsorbing recirculating system-MARS, has any effect on pruritus of cholestasis.Four patients with primary biliary cirrhosis and resistant pruritus were treated with two 7-h ECAD sessions 1 day apart. Pruritus was recorded from 15 days before the first session, before and after each session, and during the follow-up using a visual analogue scale (VAS). Standard liver tests as well as serum bile acid levels were also measured.There was a clear association between ECAD treatment and relief of itching, which promptly disappeared in two patients, or decreased markedly in the other two. One patient was free of pruritus for 18 months except for short periods with mild pruritus. The second patient experienced amelioration of itching, which almost disappeared completely and recurred mildly 4 months later. In the other two patients pruritus was alleviated markedly after ECAD but gradually recurred. These two patients were treated again 9 and 7 months later with favorable effects on pruritus. The scratching skin lesions improved or disappeared in parallel with the alleviation of itching. The albumin dialysis procedure did not result in liver test changes, except for circulating bile acids, which decreased in all the patients. No significant adverse effects were observed.The ECAD procedure seems to be an effective alternative for the treatment of patients with pruritus of cholestasis who do not respond to other therapeutic methods.

Background & Aims: Portal hypertension is a frequent syndrome that develops in patients with chronic liver diseases, which are one of the most common causes of death in adults worldwide. The most serious clinical consequences of portal hypertension are related to the development of portal-systemic collateral vessels. Those include hepatic encephalopathy and massive bleeding from ruptured gastroesophageal varices. The high relevance of these collateral vessels prompted us to investigate the mechanism underlying its formation in a murine model of portal hypertension. Methods: To determine whether the development of portal-systemic collateral vessels in portal hypertension is a vascular endothelial growth factor (VEGF)-dependent angiogenic process, we assessed the effects of a monoclonal antibody against VEGF receptor-2 on the formation of these collateral vessels in mice with portal hypertension induced by partial portal vein ligation. We also studied the effects of a selective and specific inhibitor of VEGF receptor-2 autophosphorylation in partial portal vein-ligated rats. Results: A significant and marked inhibition in the formation of portal-systemic collateral vessels was observed in both partial portal vein-ligated mice and rats treated with anti-VEGF receptor-2 monoclonal antibodies or with the inhibitor of VEGF receptor-2 autophosphorylation, respectively, compared with animals receiving control solutions. Conclusions: Our present study shows that formation of collateral vessels is an angiogenesis-dependent process that can be markedly inhibited by blockade of the VEGF signaling pathway. These findings will make angiogenesis a focal point of research in portal hypertension and may lead to novel approaches for therapy of patients with chronic liver diseases.

Hypersensitivity to endotoxin is a recognized feature in cirrhosis. High-density lipoproteins (HDL) have a high capacity to inactivate endotoxin. The aim was to determine if HDL reduces the effect of endotoxin on cytokine production and systemic hemodynamics in experimental cirrhosis.The study was performed in control and rats with carbon-tetrachloride induced cirrhosis with ascites. Hemodynamic parameters were determined before and after several doses of endotoxin. The effects of 25 microg/kg of endotoxin on the serum concentration of TNFalpha and mean arterial pressure (MAP) were determined after treatment with HDL (80 mg/kg) or saline.Whereas endotoxin decreased MAP only at doses of 100 and 1000 microg/kg in control rats, in cirrhotic rats significant hypotension occurred at doses of 25, 50, 100 and 1000 microg/kg. Following the administration of endotoxin (25 microg/kg) the serum levels of TNFalpha were 140 times higher in cirrhotic than in control rats (89?835+/-21?090 vs. 625+/-137 pg/ml; P0.001). Serum TNFalpha was 80% lower in cirrhotic rats pretreated with HDL (18?890+/-5012 pg/ml; P0.001) than in those pretreated with saline. The administration of endotoxin (25 microg/kg) was associated with a significant lower decrease of MAP in cirrhotic rats pretreated with HDL than in those receiving saline (11.9+/-3.5 vs. 24.7+/-4.3%; P0.05).HDL attenuates the increased effect of endotoxin on cytokine production and systemic hemodynamic in cirrhosis.

Background : Pretransplant renal function is the major determinant of survival after liver transplantation (LTx). Patients with hepatorenal syndrome (HRS) have a poor outcome after LTx compared with patients transplanted without HRS. Aim : To analyze the impact of treatment of HRS before LTx on outcome after transplantation. Methods : The outcome of patients with HRS ( n =9) treated with vasopressin analogues before LTx was compared with that of a contemporary control group of patients without HRS ( n =27) matched by age, severity of liver failure, and type of immunosuppression. Results : Cases and controls were similar with respect to pretransplantation characteristics. Three-year survival probability was similar between the two groups (HRS-treated: 100% vs control: 83%, P =0.15). No significant differences were found between the two groups with respect to the incidence of impairment of renal function after LTx (HRS-treated: 22% vs control: 30%), severe infections (22 vs 33%), acute rejection (33 vs 41%), days in Intensive Care Unit (6±1 vs 8±1), days in hospital (27±4 vs 31±4), and transfusion requirements (11±3 vs 10±2 units). Conclusions : Patients with HRS treated with vasopressin analogues before LTx have a posttransplantion outcome similar to that of patients transplanted with normal renal function. These results suggest that HRS should be treated before LTx.

Background/Aims : Cirrhotic livers exhibit endothelial dysfunction that contributes to the increased hepatic vascular resistance. The present study evaluates the role of cyclooxygenase (COX)-derived prostanoids, implicated in the pathogenesis of endothelial dysfunction in other settings, in the pathogenesis of endothelial dysfunction in cirrhotic livers. Methods : Endothelial dysfunction was evaluated by performing concentration-effect curves to acetylcholine after precontracting the liver with methoxamine in groups of control and CCl 4 -cirrhotic rat livers preincubated either with vehicle, indomethacin, the COX-1 selective inhibitor, SC-560, the COX-2 selective inhibitor, SC-236, the thromboxane A 2 receptor antagonist, SQ 29,548 or the nitric oxide (NO) synthase inhibitor N G -nitro-l-arginine. Thromboxane A 2 (TXA 2 ) production was determined in samples of the perfusate. Results : Cirrhotic livers exhibited endothelial dysfunction, as shown by the significantly lower relaxation to acetylcholine than control livers, that was totally corrected by indomethacin. COX-1 inhibition and TXA 2 blockade, but not COX-2 inhibition, also corrected endothelial dysfunction. Acetylcholine significantly increased TXA 2 production in cirrhotic but not in control livers. Indomethacin and COX-1 inhibition, but not COX-2 or NO inhibition, prevented the increased production of TXA 2 . Conclusions : An increased production of TXA 2 is involved in the pathogenesis of endothelial dysfunction in cirrhotic rat livers. This is mainly mediated by COX-1, but not by COX-2.

The quasispecies nature of hepatitis C virus (HCV) is thought to play a central role in modulating viral functions. Recent work has linked NS5A protein with viral replication, resistance to interferon (IFN), and control of cellular growth, probably through the interaction of its protein kinase R (double stranded RNA-activated protein kinase, PKR) binding domain (PKR-bd) with cellular PKR, but knowledge of how PKR-bd viral population evolves during disease progression is limited. Since we have previously described an association between amino acid composition of the PKR-bd and the presence of HCC, in this report we further investigated the dynamic behavior of viral population parameters by sequencing an average of 20 clones per sample in 27 samples from 19 untreated patients with different degrees of liver disease, 8 of whom were followed over time. Viral population parameters varied widely from patient to patient, but no differences were observed in the complexity, diversity, types of nucleotide changes, or evolutionary pattern of the quasispecies according to the stage of liver disease. In five samples, we detected “quasispecies-tails”; that is, clones whose minimum genetic distance to the remaining clones of their own quasispecies were higher than the maximum genetic distance found between any other two clones of the same sample. In summary, independent of the degree of liver disease, or the mutations detected within the consensus sequence of the PKR-bd, the NS5A of HCV presents a flexible and variable quasispecies structure that remains largely stable during the natural course of an HCV infection, highlighting the central role of NS5A protein in viral life cycle. J. Med. Virol. 71:195–204, 2003. © 2003 Wiley-Liss, Inc.

Carbon monoxide, a product of the heme-oxygenase (HO) pathway, is an important endogenous vasoactive substance. Production of CO has not been assessed in human cirrhosis. The aim of this study was to assess production of CO in patients with cirrhosis with and without spontaneous bacterial peritonitis (SBP). CO concentration in the exhaled air and blood carboxyhemoglobin (COHb) levels, as estimates of total HO activity, were determined in 16 healthy subjects, 32 noninfected cirrhotic patients (20 with ascites), and 19 patients with SBP, all nonsmokers. Noninfected cirrhotic patients had a CO concentration in the exhaled air and COHb levels significantly higher compared with values of healthy subjects (2.3 +/- 0.2 ppm vs. 0.7 +/- 0.1 ppm and 1.0% +/- 0.1% vs. 0.6% +/- 0.1%, respectively; P

Background & aims: The renin-angiotensin system plays an important role in hepatic fibrogenesis. In other organs, myofibroblasts accumulated in damaged tissues generate angiotensin II, which promotes inflammation and extracellular matrix synthesis. It is unknown whether myofibroblastic hepatic stellate cells, the main hepatic fibrogenic cell type, express the renin-angiotensin system and synthesize angiotensin II. The aim of this study was to investigate whether quiescent and activated human hepatic stellate cells contain the components of the renin–angiotensin system and synthesize angiotensin II. Methods: Hepatic stellate cells were freshly isolated from normal human livers (quiescent hepatic stellate cells) and from human cirrhotic livers (in vivo activated hepatic stellate cells). Culture-activated hepatic stellate cells were used after a second passage of quiescent hepatic stellate cells. Angiotensinogen, renin, and angiotensin-converting enzyme were assessed by quantitative polymerase chain reaction. Angiotensin II production was assessed by enzyme-linked immunosorbent assay and immunohistochemistry. Results: Quiescent hepatic stellate cells barely express the renin-angiotensin system components—angiotensinogen, renin, and angiotensin-converting enzyme—and do not secrete angiotensin II. In contrast, both in vivo activated hepatic stellate cells and culture-activated hepatic stellate cells highly express active renin and angiotensin-converting enzyme and secrete angiotensin II to the culture media. Mature angiotensin II protein is also detected in the cytoplasm of in vivo activated and culture-activated hepatic stellate cells. Growth factors (platelet-derived growth factor and epidermal growth factor) and vasoconstrictor substances (endothelin-1 and thrombin) stimulate angiotensin II synthesis, whereas transforming growth factor-β and proinflammatory cytokines have no effect. Vasodilator substances markedly attenuate the effect of endothelin-1. Conclusions: After activation, human hepatic stellate cells express the components of the renin-angiotensin system and synthesize angiotensin II. These results suggest that locally generated angiotensin II could participate in tissue remodeling in the human liver.

Vascular remodeling is an active process that consists in important modifications in the vessel wall. Endothelium-derived nitric oxide (NO) plays a major role in this phenomenon. We assessed wall thickness (WT), total wall area (TWA), lumen diameter, and total nuclei number/cross-section (TN) in cirrhotic rats with ascites and in control rats. A second group of cirrhotic rats received the NO synthesis inhibitor, L-NAME, or vehicle daily for 11 weeks and systemic hemodynamics, arterial compliance, aortic NO synthase 3 (NOS3) protein expression, and vascular morphology were analyzed. Cirrhotic vessels showed a significant reduction in WT, TWA, and TN as compared to control vessels. Long-term inhibition of NOS activity in cirrhotic rats resulted in a significant increase in WT, TWA, and TN as compared to cirrhotic rats receiving vehicle. NOS3 protein abundance was higher in aortic vessels of nontreated cirrhotic animals than in controls. This difference was abolished by chronic treatment with L-NAME. NOS inhibition in cirrhotic rats resulted in higher arterial pressure and peripheral resistance and lower arterial compliance than cirrhotic rats receiving vehicle. Therefore, vascular remodeling in cirrhosis with ascites is a generalized process with significant functional consequences that can be negatively modulated by long-term inhibition of NOS activity.

Background/Aims : The efficacy and safety of rifaximin in comparison with lactitol in the treatment of acute hepatic encephalopathy was assessed in a prospective randomized, double-blind, double-dummy, controlled trial. Methods : A total of 103 patients with grade I–III acute hepatic encephalopathy were randomized to receive rifaximin (50 patients, 1200 mg/day) or lactitol (53 patients, 60 g/day) for 5–10 days. Changes in the portal-systemic encephalopathy (PSE) index on entry and at the end of the study were used to evaluate the efficacy of the two therapies. Results : Both groups were comparable before treatment with regard to demographic data and characteristics of the hepatic encephalopathy episode. The global efficacy of both therapies was similar: 81.6% in the rifaximin group and 80.4% in the lactitol group showed improvement or total regression of the episode. A significantly better evolution of the PSE index was observed in the rifaximin group, due to a greater effect of rifaximin in two components of the index: EEG abnormalities and ammonia levels. No serious adverse events related to either treatment were found during the study. Conclusions : Rifaximin may be considered a useful and safe alternative therapy to lactitol in the treatment of acute hepatic encephalopathy in cirrhosis.

Background & Aims: The aim of this study was to investigate if the variable outcome of chronic hepatitis B may be related to hepatitis B virus (HBV) genotype. Methods: The clinical and virologic events observed over prolonged follow-up in 258 Spanish patients with chronic hepatitis B infected with different genotypes of HBV were compared. Results: The prevalence of genotype A, D, and F was 52%, 35%, and 7%, respectively. Concomitant sustained biochemical remission and clearance of HBV DNA occurred at a higher rate in genotype A– than in genotype D– (log-rank, 14.2; P = 0.002) or genotype F–infected patients (log-rank, 4.2; P = 0.03). The rate of hepatitis B surface antigen (HBsAg) clearance was higher in genotype A than in genotype D hepatitis (log-rank, 4.6; P = 0.03). Sustained remission and clearance of HBsAg were associated with infection with genotype A by Cox regression analysis. Seroconversion to antibody to hepatitis B e antigen (anti-HBe) was unrelated to HBV genotype, but the rate of sustained remission after seroconversion was higher in genotype A than in genotype D hepatitis both in patients who seroconverted to anti-HBe during follow-up (log-rank, 4.5; P = 0.03) and in patients with positive anti-HBe at baseline (log-rank, 6.66; P = 0.009). Death related to liver disease was more frequent in genotype F than in genotype A ( P = 0.02) or genotype D ( P = 0.002) hepatitis. Conclusions: The long-term outcome of chronic hepatitis B is different in patients infected with HBV genotype A, D, or F. GASTROENTEROLOGY 2002;123:1848-1856

Background & Aims: The transjugular intrahepatic portosystemic shunt (TIPS) has been shown to be more effective than repeated paracentesis plus albumin in the control of refractory ascites. However, its effect on survival and healthcare costs is still uncertain. Methods: Seventy patients with cirrhosis and refractory ascites were randomly assigned to TIPS (35 patients) or repeated paracentesis plus intravenous albumin (35 patients). The primary endpoint was survival without liver transplantation. Secondary endpoints were complications of cirrhosis and costs. Results: Twenty patients treated with TIPS and 18 treated with paracentesis died during the study period, whereas 7 patients in each group underwent liver transplantation (mean follow-up 282 ± 43 vs. 325 ± 61 days, respectively). The probability of survival without liver transplantation was 41% at 1 year and 26% at 2 years in the TIPS group, as compared with 35% and 30% in the paracentesis group ( P = 0.51). In a multivariate analysis, only baseline blood urea nitrogen levels and Child-Pugh score were independently associated with survival. Recurrence of ascites and development of hepatorenal syndrome were lower in the TIPS group compared with the paracentesis group, whereas the frequency of severe hepatic encephalopathy was greater in the TIPS group. The calculated costs were higher in the TIPS group than in the paracentesis group. Conclusions: In patients with refractory ascites, TIPS lowers the rate of ascites recurrence and the risk of developing hepatorenal syndrome. However, TIPS does not improve survival and is associated with an increased frequency of severe encephalopathy and higher costs compared with repeated paracentesis plus albumin. GASTROENTEROLOGY 2002;123:1839-1847

It is very difficult to predict new developments in hepatology so we have decided to analyse the most important issues related to three clinical conditions in hepatology. The first is chronic hepatitis. Here, we discuss the relevance of occult forms of hepatitis B virus infection in the development of cryptogenic liver disease and hepatocellular carcinoma. In addition, the role of genotyping in hepatitis B is analysed, indicating that patients with genotype A have a better prognosis than those with genotype D. The treatment of hepatitis B virus infection is also reviewed, and it has been suggested that research should be directed towards the development of new anti-viral agents to suppress virus replication. The natural history of hepatitis C virus infection is considered, emphasizing the need to know the progression of fibrosis in these patients. The chapter also suggests that treatment of hepatitis C virus infection with pegilated interferon and ribavirin is currently relatively effective. New therapeutic strategies will be required in the future, the most important challenge being the development of a hepatitis C virus vaccine. The second section is on chronic cholestasis. The role of anti-mitochondrial antibodies in primary biliary cirrhosis is considered. The possible infectious agents implicated as potential triggers of primary biliary cirrhosis are also discussed, suggesting that several infections may play a role in the pathogenesis of this condition. Other aetiopathogenic factors, for example organic compounds, drugs and chemicals, are indicated. It is possible that, in the near future, the precise sequence and molecular basis by which infectious agents or xenobiotics may initiate the cascade of the autoimmune response will be defined. One of the most important challenges in primary sclerosing cholangitis concerns the mechanisms that may induce the development of this disease. Up until now, genetic factors have been suggested, recent data reporting a clear-cut association between primary sclerosing cholangitis and the tumour necrosis factor-alpha(2) allele. The third part of this chapter includes recent progress achieved in hepatocellular carcinoma, discussing developments in the knowledge of hepatocellular carcinogenesis. Hepatocellular carcinomas appear so far to be genetically heterogeneous neoplasms, and this heterogeneity may correlate with the variety of aetiological factors involved. The risk factors and primary, secondary and tertiary prevention of the condition are also analysed. Finally, the development of new therapeutic strategies for hepatocellular carcinoma is evaluated by evidence-based studies.

The aim of the investigation was to assess whether hypoxia induces the production of endogenous vasoactive peptides in macrophages of cirrhotic patients with ascites because low tissue oxygenation is a relatively frequent event in these patients. Peritoneal macrophages were isolated from ascites, seeded on well plates, and cultured at different times under hypoxic (5% O2) or normoxic conditions (21% O2). Then, accumulation of vasoactive peptides sensitive to hypoxia including endothelin-1 (ET-1), vascular endothelial growth factor (VEGF), and adrenomedullin (ADM) was measured. Only VEGF and ADM were constitutively secreted, and hypoxia further stimulated the release of these vasodilator peptides. In concordance, increased messenger RNA (mRNA) levels of VEGF and ADM were found at culturing macrophages in hypoxia. This characteristic response was not observed in circulating monocytes of either cirrhotic patients or healthy subjects. Next the expression of the transcription factor, hypoxia inducible factor 1 (HIF-1), was analyzed. Expression of HIF-1α and HIF-1β messengers and HIF-1β protein subunit remained unchanged regardless of O2 tension, whereas HIF-1α protein subunit was overexpressed under hypoxic conditions. Moreover, conditioned medium from macrophages cultured under hypoxic conditions promoted a larger nitric oxide (NO) release in endothelial cells than that of normoxic macrophages. In conclusion, these data indicate that hypoxia induces the synthesis of VEGF and ADM in macrophages of cirrhotic patients, likely through HIF-1–enhanced transcriptional activity. These data suggest that a local reduction in O2 tension could enhance the synthesis of macrophage-derived vasodilators, thus aggravating the circulatory disturbance of these patients. (HEPATOLOGY 2002;36:1172-1179.)

Vasopressin analogues associated with albumin improve renal function in hepatorenal syndrome (HRS). The current study was aimed at assessing the efficacy of the treatment, predictive factors of response, recurrence of HRS, and survival after therapy. Twenty-one consecutive patients with HRS (16 with type 1 HRS, 5 with type 2 HRS) received terlipressin (0.5-2 mg/4 hours intravenously) until complete response was achieved (serum creatinine level < 1.5 mg/dL) or for 15 days; 13 patients received intravenous albumin together with terlipressin. Twelve of the 21 patients (57%) showed complete response. Albumin administration was the only predictive factor of complete response (77% in patients receiving terlipressin and albumin vs. 25% in those receiving terlipressin alone, P =.03). Treatment with terlipressin and albumin was associated with a remarkable decrease in serum creatinine level, increase in arterial pressure, and suppression of the renin-aldosterone system. By contrast, no significant changes in these parameters were found in patients treated with terlipressin alone. Only 1 patient showed ischemic adverse effects. Recurrence of HRS occurred in 17% of patients with complete response. The occurrence of complete response was associated with an improved survival. In conclusion, terlipressin therapy reverses HRS in a high proportion of patients. Recurrence rate after treatment withdrawal is uncommon. Albumin appears to improve markedly the beneficial effects of terlipressin.

Liver biopsy is required for staging hepatic fibrosis in patients with chronic hepatitis C, but it is an expensive procedure with occasional complications and poor patient acceptance. This cohort study was designed to assess the accuracy of a noninvasive method aimed to discriminate between patients with and without significant liver fibrosis (stages 2-4 versus 0-1). Clinically relevant variables were analyzed in a cohort of 476 consecutive untreated patients (estimation group, 351 patients; validation group, 125 patients) with chronic hepatitis C who underwent a liver biopsy. Multivariate analysis identified age, gamma glutamyl transpeptidase (GGT), cholesterol, platelet count, and prothrombin time as independent predictors of fibrosis. We constructed a model and a score system combining age, GGT, cholesterol, and platelet count that proved useful to identify patients without significant hepatic fibrosis. The area under the ROC curve was 0.86 for the estimation group and 0.81 for the validation group. Using the best cutoff score (less than 4.2), presence of significant fibrosis (F2 to F4) could be excluded with high accuracy (negative predictive value of 96%) in 125 (36%) of 351 patients. Similarly, it could be excluded with the same certainty in 49 (39%) of the 125 patients of the validation group. Only 2 patients with liver fibrosis stage 2 were incorrectly classified. In conclusion, a combination of easily accessible variables accurately predicts the absence of significant fibrosis and might render liver biopsy unnecessary in more than one third of patients with chronic hepatitis C.

Background/Aims : Prophylaxis of spontaneous bacterial peritonitis in cirrhotic patients with norfloxacin is associated with emergence of quinolone-resistant Enterobacteriaceae . We investigated whether an alternative strategy with Lactobacillus prevents bacterial translocation and ascitic fluid infection in cirrhotic rats. Methods : CCl 4 -induced cirrhotic rats with ascites ( n =34) were allocated to treatment with oral Lactobacillus strain GG at 1–2×10 9 cfu/day for 8–10 days (group LGG) or milk (group MILK). In addition, 20 cirrhotic rats were given a single dose of 15 mg norfloxacin orally and then allocated to Lactobacillus (group NOR-LGG) or milk (group NOR-MILK). Ten healthy rats served as control. After sacrifice the cecal flora were analyzed and the prevalence of bacterial translocation and ascitic fluid infection assessed. Results : Cecal colonization with Lactobacillus was achieved in 90% of treated rats. The prevalence of bacterial translocation to mesenteric lymph nodes was 10% in control rats and 93, 84, 70 and 100% in groups MILK, LGG, NOR-MILK and NOR-LGG, respectively ( P >0.1 for comparison of treatment groups), the prevalence of ascitic fluid infection was 60, 32, 40 and 40% ( P >0.1). Bacterial translocation of Lactobacillus was observed in 24% of rats treated. Conclusions : Lactobacilli fail to prevent bacterial translocation and ascitic fluid infection in experimental cirrhosis in spite of successful intestinal colonization.

The study of hepatitis C virus (HCV) kinetics after liver transplantation (LT) might be important to design strategies to prevent HCV infection of the graft. We analyzed HCV kinetics during and immediately after LT in 20 consecutive patients undergoing LT for HCV-related cirrhosis. HCV RNA was quantified in blood samples obtained at regular intervals before, during, and after transplantation. HCV-RNA concentrations decreased in 18 of 20 patients during the anhepatic phase (mean decay slope −0.92, mean HCV elimination half-life 2.2 hours). We found a significant correlation between the HCV viral load decay and the blood loss during the anhepatic phase, indicating that the observed HCV clearance rates are maximum estimates. In fact, in 1 patient with an unusually long anhepatic phase of 20 hours and with minimum blood loss, the HCV elimination half-life was 10.3 hours. Eight to 24 hours after graft reperfusion a sharp decrease in HCV viral load occurred in 19 patients (mean decay slope −0.34, mean HCV elimination half-life 3.44 hours). HCV RNA became undetectable in only 1 patient. During the following days, HCV-RNA concentrations increased rapidly in 10 patients (mean HCV doubling time 13.8 hours), remained at similar levels in 4, and continued to decrease in 6. The only variable associated with a second-phase viral load decay was the absence of corticosteroids as part of the immunosuppressive regimen. In conclusion, a sharp decrease in HCV viral load occurs during the anhepatic phase and immediately after graft reperfusion, most likely owing to a lack of virion production and hepatic viral clearance. HCV infection of the graft, however, is an extremely dynamic process and viral replication begins a few hours after LT. (HEPATOLOGY 2002;35:680-687.)

To investigate the relationship between neuropeptide Y (NPY), a potent renal vasoconstrictor peptide released upon marked stimulations of sympathetic nervous system (SNS), and renal and circulatory function in cirrhosis.Plasma levels of NPY (radioimmunoassay) and norepinephrine and renal function parameters were determined in 17 healthy controls, nine patients with cirrhosis without ascites, and 37 patients with cirrhosis and ascites, of whom 12 had hepatorenal syndrome (HRS).Patients with ascites showed circulating levels of NPY similar to those of patients without ascites and controls (73+/-4, +/-4 and 68+/-4 pmol/l, respectively; NS). However, patients with HRS had significantly increased levels of NPY with respect to the other groups (110+/-6 pmol/l; P0.001). NPY levels correlated inversely with renal plasma flow and glomerular filtration rate and directly with norepinephrine. In patients with HRS (n=6) treatment with terlipressin and albumin was associated with a marked improvement in circulatory and renal function and marked suppression of NPY and norepinephrine levels.Patients with HRS have increased levels of NPY which are related to circulatory dysfunction and SNS activation and may contribute to renal vasoconstriction.

Background & Aims: Cysteinyl-leukotrienes (Cys-LTs) increase intrahepatic vascular resistance in normal rat livers. CCl 4 cirrhotic rat livers have increased Cys-LT production and 5-lipoxygenase messenger RNA (mRNA) expression. The aim of this study was to investigate the role of 5-lipoxygenase–derived eicosanoids regulating intrahepatic vascular tone in control and CCl 4 -induced cirrhotic rat livers. Methods: In different groups of portally perfused control and cirrhotic rat livers, the following were analyzed: a portal perfusion pressure (PP) dose–response curve to LTD 4 ; the effects on PP caused by either vehicle, the selective 5-lipoxygenase inhibitor AA-861, the selective Cys-LT 1 receptor antagonist MK-571, or the dual Cys-LT 1 and Cys-LT 2 receptor antagonist BAY u9773; and immunohistochemistry for 5-lipoxygenase in liver sections of cirrhotic and control livers. Results: Cirrhotic livers have a hyperesponse to LTD 4 . In control livers, AA-861 and MK-571 produced a moderate and similar reduction in PP. In cirrhotic livers, 5-lipoxygenase inhibition produced a marked and significantly greater reduction in PP than in controls. However, no effect on PP was observed after MK-571 or BAY u9773. 5-Lipoxygenase–positive cells were markedly increased in cirrhotic livers. Conclusions: Our results suggest that 5-lipoxygenase–derived eicosanoids may contribute to the increased intrahepatic vascular resistance of cirrhotic rat livers and therefore the pathogenesis of portal hypertension. GASTROENTEROLOGY 2002;122:387-393

Patients with Budd-Chiari syndrome (BCS) may require treatment with portal decompressive surgery or liver transplantation. Transjugular intrahepatic portosystemic shunt (TIPS) represents a new treatment alternative, but its long-term effect on BCS outcome has not been evaluated. Twenty-one patients with BCS consecutively admitted to our unit were evaluated. The mean follow-up was 4 +/- 3 years. Seven patients had nonprogressive forms and were successfully controlled with medical therapy; 1 case, with a short-length hepatic vein stenosis was successfully treated by angioplasty. All 8 patients are alive and asymptomatic. The remaining 13 patients, had a TIPS because of clinical deterioration (in one of them, because early TIPS thrombosis a successful side-to-side portacaval shunt [SSPCS] was performed) followed by an improvement in clinical condition. However, a patient with fulminant liver failure before TIPS insertion, died 4 months later and another patient with cirrhosis at diagnosis had liver transplantation 2 years later. The remaining 11 patients are alive and free of ascites. In 3 of these patients TIPS is patent after 3, 6, and 12 months. The remaining 8 patients developed late TIPS dysfunction. In two of these cases, after angioplasty and restenting, TIPS is patent after a follow-up of 9 and 80 months. In 5 other patients, recurring TIPS occlusion was not further corrected because no signs of portal hypertension were present. In conclusion, in patients with BCS uncontrolled with medical therapy, TIPS is a highly effective technique that is associated with long-term survival.

Background & Aims: Recent studies have described the existence of endogenous cannabinoids with vasodilator activity because of their interaction with peripheral CB1 receptors, anandamide being the most extensively investigated. The study investigated whether endogenous cannabinoids are involved in the pathogenesis of the cardiovascular disturbances in experimental cirrhosis. Methods: Arterial pressure, cardiac output, and total peripheral resistance were measured before and after the administration of a cannabinoid CB1 receptor antagonist to cirrhotic rats with ascites and to control rats. Blood pressure was also assessed in normotensive recipient rats after the intravenous administration of blood cells or isolated monocytes obtained from cirrhotic and control rats. Moreover, the endogenous content of anandamide was measured in circulating monocytes of cirrhotic and control rats by gas chromatography/mass spectrometry. Results: CB1 receptor blockade did not modify systemic hemodynamics in control rats, but significantly increased arterial pressure and peripheral resistance in cirrhotic animals. Blood cell suspension or monocytes from cirrhotic animals, but not from controls, induced arterial hypotension in recipient rats. Finally, anandamide was solely detected in monocytes of cirrhotic animals. Conclusions: Monocytes of cirrhotic rats with ascites are activated to produce anandamide and this substance contributes to arterial hypotension in experimental cirrhosis.

Our aim was to compare weekly rufloxacin with daily norfloxacin in the secondary prophylaxis of spontaneous bacterial peritonitis and to examine changes in antibiotic susceptibility in fecal Eschericia coli. The method used was an open randomized clinical trial including 79 patients who received either norfloxacin 400 mg/day or rufloxacin 400 mg/week and followed up for one year. E. coli counts, quinolone susceptibility, and drug concentrations in feces were investigated in 12 patients. Cumulative one-year probability of peritonitis recurrence was 26% for patients on norfloxacin and 36% for those on rufloxacin (P = 0.16). Norfloxacin was more effective in the prevention of peritonitis recurrence due to Enterobacteriaceae (0% vs 22%, P = .01). At the end of follow-up, all 12 patients had E. coli resistant to quinolones in their feces. In conclusion, weekly rufloxacin is not an alternative to daily norfloxacin in the prevention of peritonitis recurrence. The development of quinolone-resistant E. coli in feces may be an important problem in patients on long-term quinolone prophylaxis.