Satoshi Shakado

Cultured rat hepatic sinusoidal endothelial cells express intercellular adhesion molecule-1 (ICAM-1) by tumor necrosis factor-α or interleukin-1α stimulation

This study investigated the expression of intercellular adhesion molecule-1, a leukocyte adhesion molecule, on cultured rat hepatic sinusoidal endothelial cells during stimulation with tumor necrosis factor- α or interleukin-1 α . Using immunoelectron microscopy and the immunogold technique against intercellular adhesion molecule-1, gold particles were shown to increase significantly on the surface of sinusoidal epithelial cells treated with tumor necrosis factor- α (100 U/ml) or interleukin-1 α (10 U/ml) for 8 h compared with unstimulated cells. In addition, semi-quantitative analysis of intercellular adhesion molecule-1 on the sinusoidal endothelial cells was performed by cytofluorometer. Even without stimulation, intercellular adhesion molecule-1 was weakly expressed. However, 8 h after tumor necrosis factor- α or interleukin-1 α treatment, the expression of intercellular adhesion molecule-1 on cells was increased in a dose-dependent manner. Kinetic analysis showed that the expression of intercellular adhesion molecule-1 on sinusoidal endothelial cells treated with these cytokines increased gradually from the beginning of stimulation to 24 h. These findings suggest that hepatic sinusoidal endothelial cells may mediate the direct interaction between leukocytes and sinusoidal endothelial cells by expressing leukocyte adhesion molecules such as intercellular adhesion molecule-1.

Levels of the Oxidative Stress Marker γ-Glutamyltranspeptidase at Different Stages of Nonalcoholic Fatty Liver Disease

OBJECTIVES: This study investigated oxidative stress in the liver, by determining hepatic expression and serum levels of γ-glutamyltranspeptidase (GGT) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in different stages of nonalcoholic fatty liver disease (NAFLD), and assessed whether GGT can differentiate between the various stages of NAFLD. METHODS: Expression of GGT and 8-OHdG was examined in biopsy specimens by immunohistochemistry, and serum GGT and 8-OHdG levels were measured by enzyme-linked immunosorbent assays in patients with simple fatty liver (n = 10), nonalcoholic steatohepatitis (NASH; n = 10) and, as a control, in alcoholic liver disease (ALD; n = 10). RESULTS: Hepatic tissue expression of GGT and 8-OHdG was seen in ALD, NASH and fatty liver patients. The percentage of hepatocytes positive for 8-OHdG expression and serum 8-OHdG levels was significantly higher in patients with NASH than simple fatty liver. Serum GGT levels were increased in all cases with ALD, NASH and fatty liver, and correlated significantly with serum levels of 8-OHdG in ALD and NASH, but not in simple fatty liver. CONCLUSIONS: Levels of GGT in fatty liver patients may compensate for mild oxidative stress by repressing 8-OHdG levels and preventing progression to NASH; however further oxidative stress leads to increased levels of 8-OHdG and the development of NASH.

Bafilomycin A1, a specific inhibitor of vacuolar-type H+-ATPases, inhibits the receptor-mediated endocytosis of asialoglycoproteins in isolated rat hepatocytes

BACKGROUND/METHODS The role of vacuolar type H(+)-ATPases (v-ATPases) and pH gradient between the endocytic compartments and cytoplasm in the endocytosis of asialoglycoproteins was morphologically investigated in isolated rat hepatocytes using bafilomycin A1, a specific inhibitor of v-ATPases. RESULTS Fluorescent staining by acridine orange showed that bafilomycin A2 inhibited the acidification of the endocytic compartments. Uptake of gold-conjugated asialofetuin was significantly inhibited by bafilomycin A1. However, bafilomycin A1 did not significantly inhibit uptake of a fluid phase marker, horseradish peroxidase. The number of autophagic vacuoles increased after the bafilomycin A1 treatment. However, materials in the autophagic vacuoles were rapidly degraded after the removal of bafilomycin A1. CONCLUSIONS Results suggest that: (a) v-ATPases are necessary for acidification of the endocytic compartments; (b) the pH gradient between the endocytic compartments and the cytoplasm which is generated by v-ATPases is necessary for the receptor-mediated endocytosis of asialoglycoproteins, and (c) v-ATPases may contribute to the degradation of the materials in autophagic vacuoles.

Late‐evening snack with branched‐chain amino acids improves liver function after radiofrequency ablation for hepatocellular carcinoma

Aim:  This prospective study was designed to examine whether consumption of a branched‐chain amino acid (BCAA)‐enriched nutrient mixture as a late‐evening snack (LES) helps maintain and/or improve liver functioning in liver cirrhosis (LC) patients who have undergone radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC).

Sustained upregulation of sodium taurocholate cotransporting polypeptide and bile salt export pump and downregulation of cholesterol 7α-hydroxylase in the liver of patients with end-stage primary biliary cirrhosis

To examine the mRNA expression of hepatobiliary transporters in primary biliary cirrhosis (PBC) patients and to compare bile acid absorption, synthesis, and efflux in patients with non-end-stage and end-stage PBC, we obtained liver samples from PBC patients by percutaneous needle biopsy. End-stage PBC was defined as follows: histological stage IV; cirrhosis; serum total bilirubin, ≥4.0 mg/dl; and Child-Pugh Class C. The mRNA expression levels of sodium taurocholate cotransporting polypeptide (NTCP), bile salt export pump (BSEP), and hepatic cholesterol 7α-hydroxylase (CYP7A1) were significantly higher in the PBC patients than in the controls (P < 0.01). The mRNA levels of NTCP and BSEP were significantly higher in the end-stage PBC patients than in the controls (P < 0.01). However, hepatic CYP7A1 mRNA expression decreased significantly (by 70%) in the patients with end-stage PBC as compared to the controls and the patients with non-end-stage PBC (P < 0.01). The hepatic expression of transporters mediating bile acid influx and efflux showed sustained elevation, whereas that of the rate-limiting enzyme for bile acid biosynthesis was attenuated in the end-stage PBC patients. Thus, mechanisms may be present preventing the accumulation of toxic bile acids in the hepatocytes of end-stage PBC patients.

Alternative transporter pathways in patients with untreated early-stage and late-stage primary biliary cirrhosis

Background/Aims: The hepatic expression of bile acid transporters is altered in experimental cholestasis and it is unclear whether regulation exists in human cholestatic diseases. We investigated the expression of genes involved in bile acid detoxification, basolateral export and nuclear factor regulation in untreated primary biliary cirrhosis (PBC).

Gadolinium‐ethoxybenzyl‐diethylenetriamine pentaacetic acid‐enhanced magnetic resonance imaging as a useful detection method for advanced primary biliary cirrhosis

In primary biliary cirrhosis (PBC), damaged hepatocytes resulting from chronic cholestasis follow a compensatory mechanism that alters hepatobiliary transporter expression to reduce the accumulation of potentially toxic compounds such as bile acid. Organic anion transporter peptide 1B3 (OATP1B3), which transports agents such as gadolinium‐ethoxybenzyl‐diethylenetriamine pentaacetic acid (Gd‐EOB‐DTPA), has reduced expression in the late stages of PBC. Therefore, we investigated the use of Gd‐EOB‐DTPA‐enhanced magnetic resonance imaging (MRI) as a useful detection method for the advanced staging of PBC.

Vascular endothelial growth factor reduces Fas-mediated acute liver injury in mice

Background and Aim:  Fulminant hepatitis is still a fatal liver disease, and no specific treatment for it has been available. Vascular endothelial growth factor (VEGF) is the focus of attention because of its various actions. We investigated the effect of vascular endothelial growth factor (VEGF) on Fas‐induced fulminant hepatic failure (FHF).

Spontaneous rupture of metastatic α-fetoprotein-producing gastric cancer of the liver

An 80-year-old man was admitted to our hospital because of the rupture of the liver. Laboratory data showed iron-deficiency anemia, although there was no liver dysfunction. A computed tomography scan showed large liver tumor with intraperitoneal hemorrhage, and since a serum level of α-fetoprotein (AFP) was extremely high, we initially suspected a rupture of hepatocellular carcinoma (HCC). Transarterial embolization was performed to stop bleeding from the tumor, followed by an endoscopic examination that revealed advanced gastric cancer. Histological analysis revealed that both the gastric and the hepatic tumors were moderately to poorly differentiated adenocarcinoma, as well as that both tumors were immunohistochemically positive for AFP. Finally, we diagnosed AFP-producing gastric cancer associated with liver metastasis. Rupture of metastatic liver cancer is rare, and accordingly, distinction from HCC is important, particularly for the cases of AFP-producing gastric cancer.

Non-response to daclatasvir and asunaprevir therapy in patients co-infected with hepatitis C virus genotypes 1 and 2.

Direct‐acting antiviral agents for hepatitis C virus (HCV) have been developed such as combined daclatasvir (DCV) and asunaprevir (ASV) treatment. This typically enables HCV serotype 1 patients to achieve a high sustained virological response rate, but a small number of such patients fail to respond to therapy. We investigated three HCV patients who showed no response to DCV and ASV therapy. Hepatitis C genotyping was undertaken in the three patients using nested polymerase chain reaction and polymerase chain reaction direct sequencing in the core region of the HCV genome. All three patients possessed HCV serotype 1, and no mutations were identified in either the non‐structural protein 3 or 5A region. The three patients were shown to be co‐infected with HCV genotypes 1 and 2 because genotypes 2a and 2b were also identified. This is the first report into failed response to DCV and ASV therapy in patients co‐infected with HCV genotypes 1 and 2.