Shinichiro Horiike

Hepatic iron accumulation is associated with disease progression and resistance to interferon/ribavirin combination therapy in chronic hepatitis C

Background and Aims:  Liver iron accumulation in patients with chronic hepatitis C (CHC) has received increasing attention in recent years. The aim of this study was to determine the prevalence and severity of liver iron deposition in CHC, to assess its relationship with clinical, biochemical and histological characteristics, and to study its influence on the response to interferon (IFN) plus ribavirin combination therapy.

Hepatic oxidative DNA damage is associated with increased risk for hepatocellular carcinoma in chronic hepatitis C

Although the oxidative stress frequently occurs in patients with chronic hepatitis C, its role in future hepatocellular carcinoma (HCC) development is unknown. Hepatic 8-hydroxydeoxyguanosine (8-OHdG) was quantified using liver biopsy samples from 118 naïve patients who underwent liver biopsy from 1995 to 2001. The predictability of 8-OHdG for future HCC development and its relations to epidemiologic, biochemical and histological baseline characteristics were evaluated. During the follow-up period (mean was 6.7±3.3 years), HCC was identified in 36 patients (30.5%). Univariate analysis revealed that 16 variables, including 8-OHdG counts (65.2±20.2 vs 40.0±23.5 cells per 105 μm2, P<0.0001), were significantly different between patients with and without HCC. Cox proportional hazard analysis showed that the hepatic 8-OHdG (P=0.0058) and fibrosis (P=0.0181) were independent predicting factors of HCC. Remarkably, 8-OHdG levels were positively correlated with body and hepatic iron storage markers (vs ferritin, P<0.0001 vs hepatic iron score, P<0.0001). This study showed that oxidative DNA damage is associated with increased risk for HCC and hepatic 8-OHdG levels are useful as markers to identify the extreme high-risk subgroup. The strong correlation between hepatic DNA damage and iron overload suggests that the iron content may be a strong mediator of oxidative stress and iron reduction may reduce HCC incidence in patients with chronic hepatitis C.

Effects of bezafibrate in patients with chronic hepatitis C virus infection: combination with interferon and ribavirin.

Summary.  An association of hepatitis C virus (HCV) with low‐density lipoproteins (LDL) in serum of patients with chronic hepatitis C (CHC) has been suggested. We conducted a prospective study in CHC patients complicated with hyperlipidaemia, to examine whether bezafibrate, which is commonly used for treatment of hyperlipidaemia, reduces serum HCV‐RNA titre and improves liver dysfunction. Fifteen patients received daily oral bezafibrate treatment (400 mg/day) for 8 weeks, and its effects on serum lipids, transaminases, HCV‐RNA titres, and HCV‐RNA titres bound to LDL were evaluated. Fifteen untreated patients with CHC and hyperlipidaemia were used as controls. The mean serum alanine aminotransferase levels and HCV‐RNA titres significantly decreased at the end of bezafibrate therapy in the treated group (105 ± 34 to 80 ± 32 IU/L, P = 0.02 and 2.23 ± 2.71 to 1.78 ± 2.38 × 107 copies/mL, P < 0.01 respectively), but no changes were observed in the control group. Serum HCV‐RNA titres bound to LDL, as quantified by immunoprecipitation using anti‐LDL antibody, also decreased in all 15 treated patients [5.55 ± 6.59 to 1.07 ± 1.58 × 106 copies/ml, P < 0.01 (mean reduction rate was −78.5 ± 17.0%)]. Sucrose density‐gradient ultracentrifugation study revealed that HCV‐RNA‐decreased density fractions after the bezafibrate were identical to LDL‐density fractions (1.015–1.062 g/mL). Eight CHC patients were treated with bezafibrate, interferon, and ribavirin triple therapy for 32 weeks, and four patients achieved sustained virological response to therapy. This pilot study provides further evidence of an association between HCV and LDL in serum and suggests the potential usefulness of bezafibrate as an anti‐HCV reagent for the treatment of CHC patients.

Core Protein of Hepatitis C Virus Induces Cardiomyopathy

Hepatitis C virus (HCV) has been reported to be associated with cardiomyopathy. However, the mechanism of cardiomyopathy in chronic HCV infection is still unclear. Therefore, we investigate the development of cardiomyopathy in mice transgenic for the HCV-core gene. After the age of 12 months, mice developed cardiomyopathy that appeared as left ventricular dilatation, and systolic and diastolic dysfunction assessed by Doppler echocardiography. Histologically, hypertrophy of cardiomyocytes, cardiac fibrosis, disarray and scarcity of myofibrils, vacuolization and deformity of nuclei, myofibrillar lysis, streaming of Z-bands, and an increased number of bizarre-shaped mitochondria were found in HCV-core transgenic mice. These histological changes are just consistent with cardiomyopathy. In conclusion, the HCV-core protein directly plays an important role in the development of cardiomyopathy.

Upregulation of transferrin receptor 2 and ferroportin 1 mRNA in the liver of patients with chronic hepatitis C

Background:  Iron accumulation has been reported to be associated with progression of liver injury. The mechanism of iron accumulation in the liver is not known. In the present study, hepatic messenger RNA (mRNA) expression of transferrin receptor (TfR)1, TfR2, and ferroportin (FP)1 was measured in patients with chronic hepatitis (CH).

Role of transferrin receptor 2 in hepatic accumulation of iron in patients with chronic hepatitis C

Background and Aim:  Iron deposition in the liver is a common finding in patients with chronic hepatitis C (CH‐C). The mechanism of this hepatic accumulation of iron is not completely understood. This study assessed if the protein expression of transferrin receptor 2 (TfR2) is upregulated in the liver of patients with CH‐C and if TfR2 protein mediates iron accumulation during hepatitis C virus (HCV) infection.

Circulating level of large splice variants of tenascin-C is a marker of piecemeal necrosis activity in patients with chronic hepatitis C

Abstract: Backgrounds: It has been reported that histological activity index and piecemeal necrosis are good factors to evaluate the prognosis in patients with chronic hepatitis C (CHC). Thus, there is a need for simple and noninvasive means to assess disease activity and piecemeal necrosis in patients with CHC. In this study, we measured the serum concentrations of large splice variants of tenascin‐C (cTN‐C) in patients with CHC, and examined their correlation with the degree of inflammatory activity and fibrosis as evaluated in liver biopsy specimens.

Evaluation of Cingulate Gyrus Blood Flow in Patients With Liver Cirrhosis

Although neuropsychological tests are commonly applied to detect minimal hepatic encephalopathy (HE) in patients with liver cirrhosis (LC), they provide no information about the cerebral regions involved. Recently, it has been reported that some populations of alcoholic cirrhotics, with mild HE, have reduced cerebral metabolic rate for glucose in bifrontal cortices and in the anterior cingulate gyrus. We evaluated the degree of reduction in blood flow at the anterior cingulate gyrus and the frontal lobes in cirrhotic patients who underwent single photon emission computed tomography (SPECT). Data were obtained from 47 cirrhotic patients and 47 subjects without LC. Three radiologists unaware of the results of laboratory tests visually evaluated the transaxial, coronal, and sagittal views of SPECT. The area and the degree of blood flow reduction in the anterior cingulate gyrus and frontal lobes were scored. Reduced blood flow in the anterior cingulate gyrus was observed in most LC patients. In patients without overt HE, poor performance in neuropsychological tests was correlated with reduced cerebral blood flow in the anterior cingulate gyrus. Blood flow in the anterior cingulate gyrus as measured by SPECT may be a simple and good indicator of cerebral functional changes in patients with LC.

Morphology of hepatitis C and hepatitis B virus particles as detected by immunogold electron microscopy

We performed indirect immunogold electron microscopy (EM) for immunological identification and characterization of hepatitis C virus (HCV). To clarify the morphology of HCV, an indirect immunogold EM of two plasma samples from patients with high HCV RNA titers was carried out using antibodies specific for the putative HCV envelope protein (E) 1. Spherical virus particles 55–65 nm in diameter with delicate spike projections were detected in the 1.14–1.16 g/ml fractions after sucrose density gradient centrifugation. Polyclonal and monoclonal antibodies to the putative HCV E1 specifically recognized these particles. In addition, immunogold EM of the samples was also performed to uncover the morphology of HCV core particles. Spherical particles 33–40 nm in diameter (average, 37 nm) were detected in the 1.22- to 1.25-g/ml fractions by conventional EM after sucrose density gradient centrifugation. Immunogold EM using rabbit polyclonal antibody (RR8) specific for the putative HCV core protein and colloidal gold-labeled goat antirabbit IgG showed binding of the gold particles with RR8. Some of the HCV core particles showed icosahedric morphology. Optical rotation technique showed that the HCV core particles exhibit sixfold symmetry and that the length of the regular hexagon side is approximately 20 nm, suggesting that they have an icosahedric structure. Further, the detection limit of the indirect immunogold EM was evaluated in 11 plasma samples from chronic hepatitis B patients with different degrees of hepatitis B virus (HBV) DNA titers using antihepatitis B surface antigen antibody. The study showed that the detection limit of virus using this method is 107 virions/ml.

Hepatitis C virus free-virion and immune-complex dynamics during interferon therapy with and without ribavirin in genotype-1b chronic hepatitis C patients

Summary.  The Synergistic effect of interferon (IFN) and ribavirin for patients with chronic hepatitis C has been demonstrated, but ribavirin has no apparent direct antiviral effect against hepatitis C virus (HCV) when used as monotherapy. To elucidate the mechanism of ribavirin on enhanced HCV eradication when used in combination therapy, we investigated the serum HCV dynamics of free‐virions (FV) and immune‐complexes (IC) in genotype‐1b infected patients treated with IFN‐α2b alone (n = 11) or in combination with ribavirin (n = 15). Serum FV‐ and IC‐HCV RNA were separated by immunoprecipitation using anti‐human immunoglobulin and quantified serially using real‐time detection polymerase chain reaction. At the first phase (day 0–2), the decline of FV‐ and IC‐HCV RNA was similar between the two treatment groups. At the second phase (day 2–28), the decline of IC was significantly faster in patients treated with IFN plus ribavirin compared with IFN alone [exponential decay slope = 0.079 ± 0.036 vs 0.048 ± 0.027 log10/day, P = 0.0248; half‐life = 81.1 ± 21.4 vs 135.1 ± 61.4 h, P = 0.0053], although the second phase FV‐decline was not significantly different between the two treatment groups. The fast second phase decline of IC was associated with sustained virological response to therapy. These results suggest that ribavirin may modulate the humoral immune response against HCV and trigger a favourable response to IFN. In conclusion, analysis of early IC‐HCV dynamics is useful for predicting the response to therapy and for understanding the mechanism of action of antiviral drugs in chronic hepatitis C patients.