Sumiko Nagoshi

Fulminant hepatitis and late onset hepatic failure in Japan

Aim:  A nationwide survey was performed to clarify the present state of fulminant hepatitis and late onset hepatic failure (LOHF) between 1998 and 2003 in Japan.

SNPs in the promoter region of the osteopontin gene as a marker predicting the efficacy of interferon-based therapies in patients with chronic hepatitis C.

BackgroundThe T-helper (Th)1 immune reaction is essential for the eradication of hepatitis C virus (HCV) during interferon (IFN) therapy in patients with chronic hepatitis C. Osteopontin is a cytokine crucial for the initiation of the Th1 response. Recently, we identified four single-nucleotide polymorphisms (SNPs) in the promoter region of the osteopontin gene (OPN), at nucleotide (nt) -155, -443, -616, and -1748, and suggested that the SNP at nt -443 was a marker reflecting hepatitis activity in patients with HCV. Therefore, we examined the possibility that SNPs in OPN were also markers predicting the therapeutic efficacy of IFN in patients with chronic hepatitis C.MethodsBlood was collected from 77 patients with chronic hepatitis C who had received either IFN monotherapy or IFN-ribavirin combination therapy (IFN-based therapies). SNPs in OPN, MxA, MBL, and LMP7 were analyzed by Invader assay.ResultsPromoter SNPs of OPN at nt -155, -616, and -1748 showed linkage disequilibrium at 100% to each other. Sustained virological response (SVR) was observed in 58% of all patients. The SVR rate was higher in patients with the G/G or G/A alleles in the OPN promoter SNP at nt -1748 than in those with A/A (85% vs 45%; P < 0.05). The SVR rate was also higher in patients with T/T at nt -443 than in those with C/C or C/T (86% vs 47%; P < 0.05). Such differences were particularly evident in patients with HCV genotype 1b who had a pretreatment viral load greater than 100 KIU/ml. All the patients who had G/G or G/A at nt -1748 and T/T at nt -443 obtained an SVR. On the other hand, there was no relationship between the efficacy of IFN-based therapies and SNPs in MxA, MBL, and LMP7, which had been shown to have association with the response to IFN monotherapies.ConclusionsSNPs in the promoter region of OPN may be useful as a marker to predict the efficacy of IFN-based therapies in patients with chronic hepatitis C, and further investigation regarding their real significance is warranted in a large series of patients.

Osteopontin: Versatile modulator of liver diseases

Osteopontin (OPN) is a multifunctional protein, involved in pathological conditions including inflammation, immunity, angiogenesis, fibrosis and cancer progression in various tissues. Hepatic inflammation and fibrosis induced by feeding with a diet deficient in methionine and choline (MCD diet) were markedly attenuated in OPN knockout mice when compared with wild‐type mice in the model of non‐alcoholic steatohepatitis (NASH). Hepatic cholangiocytes, myofibroblastic stellate cells and natural killer T cells were suggested to secret OPN in mice fed an MCD diet. Plasma and hepatic OPN levels were significantly higher in patients with NASH with advanced fibrosis than in those with early fibrosis. Hepatic OPN mRNA level was correlated with hepatic neutrophil infiltration and fibrosis in patients with alcoholic liver diseases. In those with hepatocellular carcinoma (HCC), OPN levels in plasma and HCC were prognostic factors after liver resection or transplantation. Downregulation of OPN inhibited tumor growth and lung metastasis in nude mice implanted with HCC cells. The single nucleotide polymorphism in the promoter region of the OPN gene was shown to be associated with activity of hepatitis in chronic hepatitis C patients, prognosis in patients with HCC, and growth and lung metastasis of HCC xenografts in nude mice. OPN was reported to be a downstream effecter of Hedgehog pathway, which modulates hepatic fibrosis and carcinogenesis. This review focuses on the roles of OPN in hepatic inflammation, fibrosis and cancer progression. Further elucidation of cellular interactions and molecular mechanisms associated with OPN actions may contribute to development of novel strategies for treatment of the liver diseases.

Increased expression of osteopontin in activated Kupffer cells and hepatic macrophages during macrophage migration in Propionibacterium acnes-treated rat liver

Abstract: Osteopontin is an extracellular matrix component that can act as a chemokine to induce macrophage migration. The significance of osteopontin in macrophage infiltration into the liver was examined in rats given heat-killed Propionibacterium acnes. In normal rats, osteopontin mRNA expression in the liver was mini-mal, determined by quantitative-competitive reverse transcription-polymerase chain reaction (RT-PCR) assay. Northern blot analysis revealed that osteopontin mRNA was not expressed in Kupffer cells isolated from normal rats. When rats received heat-killed P. acnes intravenously, marked macrophage accumulation, forming granulomas, developed in the liver later than 3 days after the injection and its extent became maximal between 5 and 7 days. In these rats, osteopontin mRNA expression was increased in the liver later than 1 day (with its peak at 3 days after the injection), and the mRNA expression was increased markedly in Kupffer cells and hepatic macrophages isolated at 7 days. The mRNA expression of monocyte chemotactic protein-1 (MCP-1) and macrophage inflammatory protein-1α (MIP-1α), chemokines for monocytes and macrophages, was also increased in the liver of P. acnes-treated rats, with peak expression at 3 days. We conclude that osteopontin derived from Kupffer cells and hepatic macrophages may contribute to the infiltration of monocytes and macrophages into the liver cooperatively with the actions of MCP-1 and MIP-1α in P. acnes-treated rats.

Re-evaluation of the Guideline published by the Acute Liver Failure Study Group of Japan in 1996 to determine the indications of liver transplantation in patients with fulminant hepatitis

Aim:  The indications for liver transplantation in cases of fulminant hepatitis are currently determined according to the Guideline of the Acute Liver Failure Study Group of Japan in 1996, which is based on assessment of the prognosis of the patients at the onset of hepatic encephalopathy and reassessed 5 days later. This Guideline was prepared based on the clinical findings in patients seen between 1988 and 1992, and showed a predictive accuracy of 82% in the patients seen between 1993 and 1995. In this study, the usefulness of the Guideline was re‐evaluated, since the therapeutic strategies for fulminant hepatitis have advanced remarkably over the last 10 years.

Massive liver necrosis after provocation of imbalance between Th1 and Th2 immune reactions in osteopontin transgenic mice.

BackgroundMassive liver necrosis can develop as a consequence of imbalance between T-helper (Th)1 and Th2 immune reactions in the liver. Osteopontin is a glycoprotein secreted for the initiation of the Th1 immune reaction, as well as for extracellular matrix formation and calcium deposition in the bone and kidney. Osteopontin is overexpressed in Kupffer cells, macrophages, and stellate cells activated in injured livers. We established transgenic mice expressing osteopontin exclusively in hepatocytes, using a vector containing human serum amyloid P component promoter. The relation of Th1/Th2 immune imbalance to massive liver necrosis was studied using these transgenic mice.MethodsTransgenic mice and C27BL/6 mice, wild-type controls of the transgenic mice, were given an intravenous injection of concanavalin-A, and the histological extent of liver injuries and plasma cytokine levels were evaluated.ResultsWhen the transgenic mice received concanavalin-A, massive necrosis and mononuclear cell infiltration developed in the liver, the extent of which was greater in the female mice than in the male mice. This treatment produced minimal liver injury and focal liver necrosis in male and female C57BL/6 mice. In these transgenic and control mice, plasma concentrations of interleukin (IL)-10 and interferon (IFN)-γ were increased after concanavalin-A treatment. However, the upregulation of plasma IL-10 concentration was smaller in the male and female transgenic mice than in the control mice, and the upregulation of the IFN-γ concentration was greater in the female transgenic mice than in the female control mice.ConclusionsTh1 and Th2 immune reactions were deranged after concanavalin-A treatment, with Th1 immunity predominating in transgenic mice expressing osteopontin in hepatocytes; this immunological imbalance may contribute to massive liver necrosis.

Regulation of hepatic macrophage function by oral administration of Xiao-Chai-Hu-Tang (Sho-saiko-to, TJ-9) in rats

The effect of Xiao-Chai-Hu-Tang (Sho-saiko-to, TJ-9), the extract of a mixture of 7 herbs, on hepatic macrophage function was studied using rats. Hepatic macrophages were activated by injection of Corynebacterium parvum or 70% partial hepatectomy. Oral administration of TJ-9 for 3 weeks did not affect the ability of these macrophages to produce superoxide anions evaluated in situ by liver perfusion with nitro blue tetrazolium (NBT) and phorbol myristate acetate (PMA). However, the similar administration of TJ-9 attenuated the blocking of the activation after partial hepatectomy produced by pretreatment with gum arabic, a polysaccharide of high molecular weight. When gum arabic was added to the medium of rat hepatic macrophages cultured with normal rat sera, their ability to produce superoxide anions was reduced in a dose-related manner. This reduction was attenuated by changing the sera to the sera obtained from rats given oral doses of TJ-9 for 3 weeks. These results suggest that TJ-9 may improve the blocked function of hepatic macrophages in activation.

Protective action of putrescine against rat liver injury.

The hepatoprotective action of orally dosed putrescine was investigated using rat models of liver injury. When rats received putrescine orally soon after a dose of carbon tetrachloride or D-galactosamine, deranged serum alanine aminotransferase values and prothrombin times were significantly attenuated compared with control levels, with improved histologic extent of liver injury. Putrescine addition to the medium of rat hepatocytes in primary culture reduced cell killing induced by D-galactosamine or the membrane detergents chenodeoxycholic acid and Triton X-100. Similar reduction was seen in cells exposed to tert-butyl hydroperoxide (TBHP), an agent producing cell death through lipid peroxidation, with attenuation of cellular malondialdehyde content. Putrescine also significantly attenuated the extent of increased plasma membrane microviscosity as assessed with 1-[4-(trimethylammonio)phenyl]-6-phenyl-1,3,5-hexatriene in TBHP-treated cells. These results suggest that orally given putrescine protects against liver injury. Plasma membrane stabilization and reduction of lipid peroxidation may contribute to this hepatoprotection.

Use of prostaglandin I2 analog in treatment of massive hepatic necrosis associated with endothelial cell injury and diffuse sinusoidal fibrin deposition

Endothelial cell damage causes massive hepatic necrosis as a result of fibrin deposition in the hepatic sinusoids. When a stable analog of prostaglandin I2, beraprost sodium, was administered to rats given either dimethylnitrosamine, carbon tetrachloride, or endotoxin followingCorynebacterium parvum administration, the hepatic necrosis produced in each was attenuated, but to a greater extent in the dimethylnitrosamine and endotoxin/Corynebacterium parvum models, where fibrin deposition in the hepatic sinusoids occurs, as compared to the carbon tetrachloride model, where such fibrin deposition does not occur. Beraprost sodium reduced the expected increase of portal venous pressure in the endotoxin/Corynebacterium parvum model without affecting plasma thrombin-antithrombin III complex levels. Beraprost sodium also significantly reduced cell killing of both isolated rat hepatocytes and hepatic sinusoidal endothelial cells exposed totert-butyl hydroperoxide when compared to controls. Beraprost sodium could prove to be a therapeutic candidate for the treatment of hepatic necrosis, particularly in cases associated with fibrin deposition in the hepatic sinusoids because of its fibrin clot-clearning action.

A case of liver cirrhosis due to hepatits C virus infection complicating giant anorectal varices treated with balloon-occluded retrograde transvenous obliteration.

A 73-year-old man with liver cirrhosis due to hepatitis C virus infection was admitted to our hospital because of massive bleeding from external varices. Colonoscopic examination revealed that giant anorectal varices had developed between the anus and rectal ampulla, and had ruptured at the perianal site. On three-dimensional computed tomography imaging, the feeding and drainage vessels of the varices were identified as the inferior mesenteric vein and right inferior hemorrhoidal vein, respectively. Endoscopic therapies were not employed for the bleeding varices, because the blood flow volume of the feeding vessel was extremely large. Balloon-occluded retrograde transvenous obliteration (B-RTO) was therefore carried out through the drainage vessels. The variceal blood flow disappeared after B-RTO therapy, and the varices decreased in size with thrombus formation verified by colonoscopy. Bleeding from the external varices also ceased. B-RTO therapy may be an effective approach for giant anorectal varices presenting as a complication in liver cirrhosis patients in whom the main drainage vessels can be determined.