Kazunobu Aso

Therapeutic efficacy of an angiotensin II receptor antagonist in patients with nonalcoholic steatohepatitis

The therapeutic efficacy of angiotensin II receptor antagonist, losartan, was studied in patients with nonalcoholic steatohepatitis (NASH). Seven patients with both NASH and hypertension were treated with losartan (50 mg/d) for 48 weeks. Treatment with losartan resulted in a significant decrease in blood markers of hepatic fibrosis, plasma TGF‐β1 and serum ferritin concentration concurrently with an improvement in serum aminotransferase levels. Histological assessment showed improvement of hepatic necroinflammation in five patients, reduction of hepatic fibrosis in four patients, and disappearance of iron deposition in two patients. No side effect of treatment was noted at any time during the study. In conclusion, the present data raise the possibility that an angiotensin II receptor antagonist may be therapeutically efficacious for NASH. (HEPATOLOGY 2004.)

Efficacy of ursodeoxycholic acid in Japanese patients with type 1 autoimmune hepatitis

Ursodeoxycholic acid (UDCA) has been shown to have beneficial effects on patients with primary biliary cirrhosis, suggesting that UDCA has immunomodulating effects. We investigated the effect of UDCA in patients with autoimmune hepatitis (AIH) which is characterized by immunological abnormalities. Eight patients with type 1 AIH were treated with 600 mg of UDCA per day for 2 years. Based on the criteria of the International Autoimmune Hepatitis Group, five patients were diagnosed as definite and three as probable type 1 AIH. Liver function tests were performed every 4 weeks, before and during UDCA therapy and the serum levels of anti‐nuclear antibodies (ANA), smooth muscle antibodies (SMA), immunoglobulin G and gamma globulin were determined every 3 months. The levels of serum aspartate aminotransferase and alanine aminotransferase significantly decreased from 154 ± 24 IU/L and 170 ± 17 IU/L before UDCA therapy to 31 ± 3 IU/L and 25 ± 5 IU/L (P < 0.001) after 1 year of treatment and 28 ± 2 IU/L and 23 ± 4 IU/L (P < 0.001) after 2 years of treatment. After 2 years of treatment, the levels of serum immunoglobulin G and gamma globulin significantly decreased (P < 0.05) and ANA titres (5/8 patients) were reduced and SMA (3/5. patients) became negative. Furthermore, hepatic histopathological changes of four patients were assessed after 1 year of treatment, and an improvement of intrahepatic inflammation, but not fibrosis, was observed. In conclusion, these results suggest that UDCA has a beneficial therapeutic effect in patients with type 1 autoimmune hepatitis.

High, but not low, molecular weight hyaluronan prevents T-cell-mediated liver injury by reducing proinflammatory cytokines in mice

BackgroundThe extracellular matrix component hyaluronan (HA) modulates the production of various cytokines and chemokines by activated inflammatory cells. In this study, we investigated whether exogenous administration of HA influences T-cell-mediated liver injury and cytokine production.MethodsLiver injury was induced by administration of concanavalin A (Con A) or D-galactosamine/lipopolysaccharide (GalN/LPS), and 0.05%–0.35% (v/v) HA (MW 250, 470, 780, 900, and 1200 kDa) was administered intravenously 18 h before Con A or GalN/LPS injection. Plasma ALT level was determined enzymatically and plasma cytokine levels were determined by ELISA.ResultsThe elevated plasma levels of ALT at 8 h after Con A and at 7 h after GalN/LPS injection were significantly decreased by pretreatment with high molecular weight HAs (780, 900, and 1200 kDa) but not low molecular weight HAs (250 and 470 kDa). High molecular weight HA (900 kDa) significantly reduced plasma tumor necrosis factor-alpha, interferon gamma, macrophage inflammatory protein 2, and interleukin 4 levels after Con A injection. However, this inhibitory effect on plasma cytokines was not observed with low molecular weight HA (250 kDa) pretreatment.ConclusionsThe present results suggest that high molecular weight but not low molecular weight HA prevents liver injury by reducing proinflammatory cytokines in a T-cell-mediated liver injury model.

Macrophage inflammatory protein-2 induced by TNF-α plays a pivotal role in concanavalin A-induced liver injury in mice

Abstract Background/Aims : Macrophage inflammatory protein-2 (MIP-2), one of the CXC chemokines, is involved in the recruitment of neutrophils in several tissue injuries. In this study, we investigated the role of MIP-2 in concanavalin A (Con A)-induced liver injury in mice. Methods : Liver injury was induced by intravenous injection of Con A (15 mg/kg) and plasma alanine aminotransferase (ALT), MIP-2 levels were determined and histological assessment of the liver was performed. Anti-mouse MIP-2 antibody was intravenously administered 30 min before Con A injection. Results : The plasma ALT level significantly elevated and reached a maximum at 8 h after Con A injection. The plasma MIP-2 level was also elevated and reached a peak value at 2 h after Con A injection. The elevated ALT level by Con A injection was significantly inhibited by the MIP-2 antibody. The elevated plasma MIP-2 level after Con A injection was significantly reduced by the tumor necrosis factor alpha (TNF- α ) antibody, and MIP-2 was induced in plasma after recombinant TNF- α injection. Hepatic necrosis and infiltration of neutrophils were observed after Con A injection, and these histological changes were attenuated by the MIP-2 antibody. Conclusions : These findings suggest that Con A induces TNF- α release, and this TNF- α stimulates MIP-2 induction, at least partially contributing to the liver injury mediated through the recruitment of neutrophils.

Antithrombin III prevents concanavalin A-induced liver injury through inhibition of macrophage inflammatory protein-2 release and production of prostacyclin in mice

BACKGROUND/AIMS Recently, we have reported that macrophage inflammatory protein-2 (MIP-2) plays a pivotal role in concanavalin A (Con A)-induced liver injury. In this study, we investigated the effect of antithrombin III (AT-III) on liver damage, and production of MIP-2 and prostacyclin in this model. METHODS Liver injury was induced by intravenous injection of Con A (15 mg/kg) and AT-III was administered (50, 250 and 500 units/kg, iv) 30 mm before Con A injection. Plasma levels of alanine aminotransferase (ALT), MIP-2 and 6-keto-prostaglandin F1alpha (6k-PG-F1alpha), stable metabolite of prostaglandin I(2) (prostacyclin), were determined. RESULTS The elevated plasma ALT levels 8, 16, 24 h after Con A injection were inhibited by AT-III pretreatment. The elevated plasma MIP-2 levels were significantly inhibited by AT-III pretreatment compared with vehicle treatment. The inhibitory effect of AT-III on plasma ALT and MIP-2 in Con A-induced liver injury was attenuated by indomethacin (5 mg/kg, ip). Plasma concentration of 6k-PG-F1alpha at 2 h after AT-III injection was significantly elevated compared with baseline and vehicle pretreatment. CONCLUSIONS These findings suggest that AT-III prevents Con A-induced liver injury through an inhibition of MIP-2 release and a production of prostacyclin.

Homeobox gene CDX2 inhibits human pancreatic cancer cell proliferation by down-regulating cyclin D1 transcriptional activity.

Objectives: Homeobox gene caudal related homeobox gene 2 (CDX2) is an intestine-specific tumor suppressor gene. This study is intended to investigate the effect of CDX2 expression on cell proliferation and cyclin D1 expression in pancreatic cancer cells. Methods: Four pancreatic ductal adenocarcinoma cell lines (PancQGO-1, BxPC-3, MIAPaCa-2, CFPAC-1), 1 islet carcinoma cell line (QGP-1), and 1 adenosquamous carcinoma cell line (KP-3) were analyzed for CDX1 and CDX2 expression using real-time reverse transcription-polymerase chain reaction and Western blot analysis. Proliferation of pancreatic cancer cells was analyzed using WST-1 assay after CDX2 transfection. Luciferase assay was performed to examine the effects of CDX2 on cyclin D1 transcriptional activity. Results: CDX2 was expressed at a significantly higher level in QGP-1 cells than in KP-3 cells. Moreover, CDX2 was expressed at a middle level in 4 pancreatic ductal adenocarcinoma cells. Cell proliferation and cyclin D1 mRNA level were inhibited significantly after CDX2 transfection in pancreatic cancer cells. Furthermore, CDX2 inhibited exogenous nuclear factor &kgr;B-p65-induced luciferase gene expression in a dose-dependent manner. In addition, CDX2 inhibited pGL2HIVD1&kgr;B2-luciferase activity. Conclusions: CDX2 might play a role in inhibiting cell proliferation and repressing cyclin D1 transcriptional activity through the proximal nuclear factor &kgr;B binding site in pancreatic cancer cells.

Effect of ursodeoxycholic acid on autoimmune-associated chronic hepatitis C

Background: Hypergammaglobulinaemia and various auto‐antibodies which are commonly seen in autoimmune hepatitis are also found in patients with chronic hepatitis C. We recently reported that ursodeoxycholic acid (UDCA) improved liver function tests and immunoserological markers in patients with type I autoimmune hepatitis. The aim of this study was to prospectively evaluate the efficacy of UDCA on autoimmune‐associated chronic hepatitis C.

Extracellular vesicle-encapsulated miR-30e suppresses cholangiocarcinoma cell invasion and migration via inhibiting epithelial-mesenchymal transition

Early-staged cholangiocarcinoma (CCA) is difficult to diagnose due to its high potential for invasion and metastasis. Epithelial-mesenchymal transition (EMT) is induced by transforming growth factor-β (TGF-β) in a process thought to be important for invasion and metastasis in several cancers, including CCA. Although microRNAs (miRNAs) have been implicated in the pathogenesis of several malignancies, their roles to CCA are not clearly understood. Some miRNAs were reported to be included in extracellular vesicles (EVs) and transferred from their donor cells to other cells, modulating recipient cell behaviors. In this study, the involvement and functional roles of EV-contained miRNAs during EMT in human CCA were determined. Expression profiling identified a subset of miRNAs that were reduced by TGF-β in CCA cells. Among these, miR-30e was highly downregulated by TGF-β and predicted to target Snail, which is an EMT-inducible transcription factor. MiR-30e overexpression suppressed cell invasion and migration via inhibiting EMT, whereas miR-30e inhibition promoted EMT, cell invasion and migration. Moreover, miR-30e was enriched in EVs derived from CCA cells after miR-30e overexpression, and miR-30e intercellular transfer through EVs suppressed EMT, cell invasion and migration in recipient CCA cells. Together, our results suggest that EV-mediated miR-30e transfer could inhibit EMT via directly targeting Snail, which subsequently suppresses CCA cell invasion and migration. These findings provide several new insights into regulatory mechanisms of tumor invasion and metastasis in human CCA.

Tu1052 Prognostic Value of Contrast-Enhanced Ultrasonography in Patients With Small Hepatocellular Carcinoma

Introduction: Epidemiological studies have shown that nonalcoholic fatty liver disease (NAFLD) not only is a possible precursor of cirrhosis, but also has been associated with metabolic syndrome, diabetes and cardiovascular disease. There is a need to find a biomarker which proves to be reliable, non-invasive, and easy to perform in clinical practice. Our aim was to know whether serum alanine aminotransferase (ALT) value is a reliable biomarker of liver fat content in subjects with NAFLD in the general population, and to determine if the current threshold of normality for ALT is appropriate to assess the presence of liver fat in these subjects. Methods: This is a cross-sectional, randomized, prospective, populationbased study. We studied 120 healthy subjects attending health screening centers, alcohol consumption less than 50 g/week. Subjects underwent blood tests including aminotransferases. Viral hepatitis, autoimmune, drugs and others causes of liver disease were excluded. Measurements: quantification of liver fat content by spectroscopy 1H MR with magnetic field strength of 3 tesla. We used a cut off value .5% of liver fat content as the upper limit of normal for the diagnosis of hepatic steatosis (1). Serum ALT levels by commercially available kits. Results: There was an excellent positive correlation between liver fat content and serum levels of ALT (r = 0.73, p ,0.0001). All subjects with ALT values .37 U/L had hepatic steatosis (PPV: 100%) and none of the subjects with ALT ,20 U/L had steatosis (NPV: 100%). ROC curves were created, obtaining that the cutoff value that represents the normal threshold for the diagnosis of NAFLD was ALT: 23 U / L (sensitivity: 94.67%, specificity 73.91%, PPV: 85.84%, NPV: 89.47%). Conclusion: This study shows that serum ALT levels could be a reliable biomarker of NAFLD if the upper limit of normal for ALT is set at 23 U/L.

Acute renal failure in a HCV cirrhotic patient receiving interferon therapy

症例は58歳, 女性. 当科にて慢性C型肝炎と診断され, 平成4, 6年にインターフェロン (IFN) 投与を受けるも肝機能障害は続き, 平成14年4月に施行した肝生検では前肝硬変への進展が確認された. 平成14年4月30日より天然型IFNαの少量長期投与を開始したが, 平成14年9月2日の受診時, 下腿浮腫およびBUN, Cr値の軽度上昇を認め, IFN投与を中止した. その後も副腎皮質ステロイドを始めとする治療に反応することなく急速に腎不全へと進展. 10月9日より血液透析を導入したが, DICを合併し, 11月21日に死亡した. 剖検ではC型肝硬変症に合併した肝性IgA腎症と診断された. 肝硬変症に糸球体病変が高率に合併するが, 一般にはあまり知られていない. IFNによる腎障害はその多くが可逆性であるが, 潜在的に腎機能障害が存在する場合は本症例のように急速に腎不全へと進行しうる. 肝硬変症へのIFN投与の適応拡大にあたり, 充分な注意が必要である.