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Background and Aim: Copeptin is a stable cleavage product of the arginine vasopressin precursor and is equimolarly secreted with arginine vasopressin. We aimed to assess whether copeptin is the surrogate marker for complications related chronic liver disease (CLD) such as ascites, hepatic encephalopathy (HE), portosystemic shunts (PSSs), and all causes of mortality in CLD., Methods: Serum copeptin was measured in 170 CLD patients upon hospital admission. The association of copeptin levels with liver enzymes, liver functional reserve, and clinical parameters was investigated. Cox proportional hazard regression, logistic regression, and Kaplan-Meier analyses were performed to evaluate the associations of copeptin and ascites, HE and PSS formation, and prognostic factors with short-term (1 year) and long-term (4 years) mortality., Results: Serum copeptin levels were significantly correlated with liver and renal function, elevated in parallel with liver disease progression, and also associated with HE. Serum copeptin, albumin-bilirubin score and hepatocellular carcinoma were independent predictors of PSS formation and decreased rate of survival. Serum copeptin and albumin-bilirubin scores were independent predictors of ascites retention. The short-term and long-term cumulative mortality rate was significantly decreased in patients with serum copeptin >5.5 or >4.8 pmol/mL compared with patients in whom serum copeptin levels were <5.5 or <4.8 pmol/mL (P < 0.0001; P < 0.0001)., Conclusions: Serum copeptin level is a predictor for ascites retention and HE and PSS formation associated with portal hypertension. Moreover, serum copeptin level may be useful in predicting the rate of survival in patients with CLD., (© 2020 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

Background and Aim: The prognosis of cirrhotic patients with hepatic edema is poor. Although several short-term predictors of tolvaptan (novel diuretic agent) treatment for such patients have been reported, the factors related to long-term survival are still unclear., Methods: Among 459 patients with hepatic edema enrolled in a retrospective, multicenter collaborative study, we analyzed 407 patients who received tolvaptan., Results: Patients consisted of 266 men and 141 women, with the median age of 68 years (range, 28-93 years). The frequency of short-term responders to tolvaptan was 59.7% (243/407). In the Cox regression analysis, short-term response to tolvaptan, low average dosages of furosemide and spironolactone during tolvaptan treatment, Child-Pugh classification A and B, and absence of hepatocellular carcinoma were independent factors contributed to 1-year survival. The 1-year and long-term cumulative survival rates in short-term responders were significantly higher than those in non-responders (P = 0.011 and 0.010, respectively). Using a receiver operating characteristic curve analysis, the optimal cut-off values of average daily dosages of furosemide and spironolactone for predicting 1-year survival were 19 and 23 mg/day, respectively. The long-term cumulative survival rates in patients who received a mean dosage of spironolactone < 23 mg/day during tolvaptan treatment were significantly higher than those receiving a mean dosage of ≥ 23 mg/day (P = 0.001)., Conclusions: The present study suggests that the short-term response to tolvaptan and low dosages of conventional diuretics during tolvaptan treatment might improve the 1-year and long-term survival rates in cirrhotic patients with hepatic edema., (© 2019 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

Treatment of non-alcoholic fatty liver disease involves not only the management of the liver disease itself but the associated metabolic risk factors as well. However, no single treatment has been shown to be universally efficacious. Effective treatment regimens directed at both decreasing insulin resistance as well as the processes of necroinflammation have been investigated and include lifestyle intervention, surgical treatment, and pharmacotherapy. Lifestyle modification, weight loss, and physical activity represent the cornerstone of treatment. Given the important role of insulin resistance in the pathophysiology of non-alcoholic steatohepatitis, thiazolidinediones are used to improve insulin resistance. Ongoing large multicenter studies will provide information about long-term efficacy and safety of pioglitazone in patients with non-alcoholic steatohepatitis. Many other medications have shown promising results in the investigations using animal models and in preliminary pilot studies. Because the sample sizes of these studies were relatively small and the durations were short, further validation is required., (© 2013 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.)

Background and Aim: Various techniques using magnifying endoscopy (ME) have been developed to enhance images of early gastric cancer (EGC) demarcations, which are often obscure. We investigated four ME methods to determine which is most effective in enhancing the recognition of EGC demarcations: conventional ME (CME), ME with narrow band imaging (NBI-ME), enhanced-magnification endoscopy with acetic acid (EME), and ME with NBI and acetic acid (NBI-EME)., Methods: Thirty-seven successive patients having a total of 40 EGCs participated in the investigation. The endoscope was fixed and magnification images of EGC demarcations in each patient were recorded using four different ME methods (CME, NBI-ME, EME and NBI-EME). Eight experts and eight non-experts scored each of the four images of each lesion for ease of recognition of demarcation (1 to 4, with 4 being easiest)., Results: The mean scores of expert and non-expert judges, respectively, for images acquired using each technique were: CME 1.23, 1.24; NBI-ME 2.61, 2.95; EME 2.62, 2.32 and NBI-EME 3.54, 3.50. There were significant differences between the mean scores for the four techniques (P < 0.0001) using one-way repeated-measures anova. In a Bonferroni's multiple comparison, the average scores (expert and non-expert) of images acquired using NBI-EME were significantly higher than those acquired using other methods; images acquired by NBI-ME or EME also scored significantly higher than those by CME. Non-experts also scored NBI-ME images significantly higher than CME and EME images., Conclusions: Early gastric cancer demarcations were recognized most easily using NBI-EME, and more easily using EME or NBI-ME than CME.

The hepatotoxic effects of alcohol have been described in detail, but mechanisms underlying the hepatotoxicity have been only partially characterized. Recently, increasing lines of evidence indicate that Kupffer cells play multiple roles in initiation and progression of alcoholic steatohepatitis. After ethanol exposure, Kupffer cells are activated via a mechanism dependent on gut-derived endotoxin, and release active mediators such as proinflammatory cytokines and eicosanoids. These mediators are responsible for the pathophysiology of alcoholic steatohepatitis. This review discusses the current concept of Kupffer cell-mediated steatohepatitis and how it relates to the hypothesis on the mechanism by which alcoholic steatohepetitis is caused, as well as several key issues that have to be addressed in this field: (i) How do Kupffer cells undergo priming and activation during alcoholic steatohepatitis?; (ii) What kind of mediators are involved?; and (iii) How does the concept translate into a strategy for therapeutics of alcoholic steatohepatitis?

Acetaminophen overdose causes liver injury by mechanisms involving glutathione depletion, oxidative stress and mitochondrial dysfunction. The role of apoptosis in acetaminophen-induced cell killing is still controversial. Here, our aim was to evaluate the mitochondrial permeability transition (MPT) as a key factor in acetaminophen-induced necrotic and apoptotic killing of primary cultured mouse hepatocytes. Acetaminophen (10 micromol/L) induced necrotic killing in approximately 50% of hepatocytes after 6 h and cyclosporin A (CsA), MPT inhibitor, temporarily decreased necrotic killing after 6 h, but cytoprotection was lost after 16 h. Confocal microscopy revealed mitochondrial depolarization and inner membrane permeabilization at approximately 4.5 h after acetaminophen. CsA delayed these changes indicative of the MPT to about 11 h after acetaminophen. TUNEL labeling and caspase 3 activation also increased after acetaminophen. Fructose (20 mmol/L, an ATP-generating glycolytic substrate) plus glycine (5 mmol/L, a membrane stabilizing amino acid) prevented nearly all necrotic cell killing but paradoxically increased apoptosis. In conclusion, acetaminophen induces the MPT and ATP-depletion-dependent necrosis or caspase-dependent apoptosis as determined, in part, by ATP availability from glycolysis.

Altered gene expression in liver sinusoidal endothelial cells (SEC) is associated with a variety of aspects of liver pathophysiology. It is, therefore, possible to envision a new therapeutic strategy for treatment of intractable liver diseases and achievement of graft-specific immunotolerance through modulation of SEC functions by genetic engineering. The SEC possesses unique hyaluronan receptors that recognize and internalize hyaluronic acid (HA). This characteristic was used in the development of a system for targeting foreign DNA to SEC. A gene carrier system was prepared by coupling HA oligomers to poly L-lysine (PLL) in a 1:1 weight ratio by reductive amination reaction. The resulting copolymer (PLL-g-HA) was mixed with various amounts of DNA in 154 mM NaCl. Inter-polyelectrolyte complex formation between PLL-g-HA and DNA exhibited minimal self-aggregation, explaining the highly soluble nature of the complex. Complex formation between PLL-g-HA and DNA was further assessed with a gel retardation assay. The titration point representing the minimum proportion of PLL-g-HA required to retard the DNA completely occurred at a 1:1 copolymer (based on PLL) to DNA charge ratio. Following intravenous injection of (32)P-labeled pSV beta-Gal plasmid complexed to PLL-g-HA in Wistar rats, >90% of the injected counts were shown to be taken up by the liver. Further, it was shown that the PLL-g-HA/DNA complex was distributed exclusively in the SEC. At 72 h after injection of 90 mug of pSV beta-Gal in a PLL-g-HA-complexed form, a large number of SEC expressing beta-galactosidase were detected. So, the PLL-g-HA/DNA system permits targeted delivery of exogenous nucleotide agents selectively to the liver SEC, providing a novel strategy for manipulation of SEC functions.

Obesity and insulin resistance are the key factors for progression of hepatic fibrosis in various chronic liver diseases including non-alcoholic steatohepatitis (NASH). Recently it has been shown that leptin plays a pivotal role in development of hepatic fibrosis. Leptin promotes hepatic fibrogenesis through upregulation of transforming growth factor-beta in Kupffer cells and sinusoidal endothelial cells. Further, leptin facilitates proliferation and prevents apoptosis of hepatic stellate cells. There is a paradox, however, in that ob/ob mice and Zucker rats, which are the obese and diabetic strains, had minimal profibrogenic responses in the liver, most likely because they lack leptin and its receptors. To establish a more clinically relevant model to study the mechanism of fibrogenesis under steatohepatitis, fatty changes and profibrogenic responses in the liver caused by methionine-choline deficiency (MCD) were investigated in the KK-A(y) mouse, which is an obese and diabetic strain. KK-A(y) mice developed more severe hepatic steatosis, inflammation and fibrosis induced by an MCD diet as compared to C57Bl/6 controls. Importantly, KK-A(y) mice lack physiological upregulation of adiponectin levels, suggesting that adiponectin plays a pivotal role not only in regulation of insulin sensitivity but also in modulation of inflammatory and profibrogenic responses in dietary steatohepatitis. Collectively, these findings support the hypothesis that the balance of adipocytokine expression is a key regulator for the progression of hepatic fibrosis in the setting of steatohepatitis.

Background: To explore therapeutic strategies for hepatocellular carcinoma (HCC) there is a need for a suitable and reproducible animal model. However, most models produced thus far have drawbacks such as high rates of artificial tumor dissemination and complexity of the implantation technique. To circumvent these issues, we selected an appropriate HCC cell line coupled with a simple modality to prevent unintended tumor cell dissemination., Method: KDH-8 cells were inoculated into the rat liver. To prevent tumor cell leakage, a human fibrinogen/thrombin-coated collagen patch was attached on the site after withdrawal of the needle. In some animals, ligation of the hepatic artery was performed., Results: Early after injection, all rats (n = 60) developed a solitary nodule. Successful inoculation was observed in all animals with a leakage (dissemination) rate of 0%. Computed tomography (CT) demonstrated a well-demarcated low density mass accompanied with a central necrosis that mimicked a typical CT image of human HCC. Doppler ultrasonography demonstrated a vascularized property of the tumor. Tumor volumes increased with time, reaching 3299.5 +/- 290.0 mm3 at day 28 after inoculation. Thus the formed KDH-8 hepatoma was pathologically classified into a poorly differentiated HCC demarcated with surrounding connective tissue. After hepatic arterial ligation, tumor growth was impeded with an inhibition of 59.1 and 70.4% (day 21 and 28, respectively)., Conclusions: The current orthotopic hepatoma model enables a controlled and reproducible tumorigenicity and displays properties and histopathology resembling human HCC. It may be a useful tool in the investigation of antiangiogenic and anticancer therapeutics.

The hepatotoxic effects of alcohol have been described in detail, but factors responsible for its hepatotoxicity have only partially been characterized. For example, it is known that chronic ethanol ingestion increases hepatotoxicity and produces fatty liver, hepatitis and cirrhosis. However, acute ethanol consumption reduces endotoxin hepatotoxicity. It now appears that Kupffer cells participate in several aspects of these phenomena. Previously, most studies on the effects of alcohol on liver function have focused chiefly on the hepatocyte. Recently, attention has been directed towards the effect of ethanol ingestion on Kupffer cell function, which is stimulated by gut-derived endotoxins (lipopolysaccharides) via mechanisms dependent on increased gut permeability and the possible relationship between Kupffer cells and alcohol-induced liver injury. Here we will review new evidence for the proposal that Kupffer cells and endotoxins play a pivotal role in hepatotoxicity following alcohol exposure, based on studies using the continuous intragastric enteral feeding model developed by Tsukamoto and French and an acute model developed by us.

Biopsy samples from patients with liver cirrhosis were investigated for changes in gastric mucosal energy metabolism and intracellular mucin content using high performance liquid chromatography and an image analysing system. The test group consisted of eight non-cirrhotic patients with endoscopically normal mucosa (controls) and eight cirrhotic patients with oesophageal varices. The amount of ATP, energy charge level and intracellular mucin content were all significantly decreased in cirrhotic patients when compared with those of the controls. The decrease in energy charge also correlated well with the decrease in intracellular mucin content in the gastric mucosa. The results indicate that gastric mucosal energy metabolism is impaired in cirrhotic patients concomitantly with a decrease in the intracellular mucin content in the gastric mucosa. These changes may weaken defensive mechanisms against acid and NSAID, resulting in gastric mucosal injury in cirrhotic patients.

Kupffer cells (KC) become activated in response to lipopolysaccharide (LPS) and produce a variety of mediators. Among them, TNF alpha is known to injure the liver. Here we report that TNF alpha mediates apoptosis in KC and sinusoidal endothelial cells. After stimulation for 24 h with LPS (0-10 micrograms/mL), apoptosis in KC detected by TUNEL TdT-mediated dUTP-biotin nick end labelling (TUNEL) increased in a concentration-dependent manner (0 micrograms/mL, 12 +/- 4%; 0.1 microgram/mL, 36 +/- 11%; 1.0 micrograms/mL, 65 +/- 9%; 10 micrograms/mL, 78 +/- 15%). In contrast, co-incubation of endothelial cells with LPS-stimulated KC resulted in a marked increase in TUNEL-positive endothelial cells. TNF alpha antibody blocked apoptosis in both KC and endothelial cells. Apoptosis was observed in cells adjacent to or in contact with KC. Reducing transmembrane TNF alpha expressed on KC also led to a decrease in endothelial cell apoptosis, suggesting that transmembrane TNF alpha is implicated in the cell-to-cell contact mechanism of induction of apoptosis. Thus, TNF alpha mediates apoptosis in KC and endothelial cells.

Non-steroidal anti-inflammatory drugs (NSAID) are, and have been, frequently used for alleviation of pain in patients; however, they are known to cause gastric mucosal injury in experimental animals and in humans. A decrease in the gastric mucosal blood flow also plays an important role in the aetiology of acute gastric mucosal injury, as we previously reported. This study investigated the effect of a newly synthesized NSAID, loxoprofen sodium (sodium 2[p-2 oxocyclopentylmethyl) phenyl]propionate dihydrate, on gastric mucosal haemodynamics using a reflectance spectrophotometry system. Both single and cross-over methods were used in five volunteer subjects. Loxoprofen sodium 60 mg (one tablet) or indomethacin 25 mg (one tablet), was diluted in 10 mL water at 25 degrees C and sprayed on the gastric mucosa via a polyethylene tube inserted into the biopsy channel of an endoscope. After drug administration, reflectance spectra were taken every 5 min for 30 min. The indices of mucosal haemoglobin content (IHb) and oxygen saturation of haemoglobin (ISO2) were determined by the method previously reported by the authors. Indomethacin administration produced a significant decrease in both IHb and ISO2 values, indication ischaemia. Loxoprofen sodium, however, showed no significant differences in either of the parameters. Haemorrhagic erosions were evident after indomethacin administration, but none were found after loxoprofen sodium administration. The conclusion reached on the basis of this evidence is that one-time topical application of loxoprofen sodium is safer than indomethacin.