International Hepatology Communications最新文献

Serum level of interleukin-1 receptor antagonist (IL-1ra) before and during interferon (IFN) therapy was measured by sandwich ELISA. Serum IL-1ra level was significantly increased in chronic hepatitis C (CH-C) patients as compared with healthy control subjects. There was no significant correlation between serum IL-1ra and ALT level. In CHC patients, IFN treatment elevated serum IL-1ra level significantly in 2 weeks after start of the treatment. The alteration of serum IL-1ra level during treatment of IFN was compared between complete responders (CR), in whom hepatitis C virus (HCV) was eradicated, transient responders (TR), whose ALT levels transiently decreased during the treatment, and relapsed and non-responders (NR), in whom the virus was not eradicated. In TR or NR, the level in 2 weeks after the start of treatment is significantly higher than that before the treatment and in 3 months after its start. In CR, however, this transient elevation of IL-1ra level was not observed. These changes of serum IL-1ra during IFN therapy might reflect the immunological or inflammatory changes of IFN-treated CHC patients and influence the efficacy of IFN therapy.

We studied the evolution of glutathione S-transferase (GST)-P gene expression during hepatocarcinogenesis in rats treated with diethylnitrosamine (DEN) by the in situ hybridization method using a complementary RNA probe. The following findings were observed. Six weeks after the DEN treatment, distinct hybridization signals showing the presence of GST-P mRNA were found in the foci of vacuolized hepatocytes. Ten weeks after the DEN treatment, the signals were found in hepatocytes within hyperplastic nodules. Fourteen weeks after the DEN treatment, there were variously differentiated hepatocellular carcinomas, with well-differentiated hepatocellular carcinoma exhibiting signals as intense as hyperplastic nodules, and poorly-differentiated hepatocellular carcinoma exhibiting even more intense signals. Thus, the expression of GST-P gene transcripts was confirmed in the foci of vacuolized hepatocytes, with variation of gene expression in accordance with carcinoma cell differentiation.

The contribution of apoptosis to hepatocyte cell death after rat liver injury from the hepatotoxin galactosamine (GalN) was examined. Histologic evidence of diffuse hepatocyte apoptosis existed after GalN administration. Since apoptosis is an active form of cell death usually requiring new gene expression, it was determined whether genes associated with apoptosis were expressed following GalN liver injury. RP-8 and TRPM-2, two genes associated with apoptosis in other organs, were expressed in normal liver, and their mRNA levels increased after GalN injury. These genes were expressed in hepatocytes without any intralobular zonal gradient in expression. In contrast to GalN liver injury, RP-8 and TRPM-2 levels were unchanged during the purely proliferative response following rat partial hepatectomy. These data suggest that hepatocytes constitutively express the genetic program for apoptosis including the RP-8 and TRPM-2 genes. The ability of toxic liver injury to further stimulate expression of these genes may lead to apoptotic hepatocyte cell death.

In this study, a covalent bilirubin-binding amino acid residue of the albumin molecule in δ bilirubin was identified. Icteric human serum was treated with a diazo reagent and bilirubin was converted to a stable azodipyrrole. Then, an albumin fraction containing an azodipryrrole-albumin covalent conjugate was obtained by affinity chromatography using Blue Sepharose CL-6B, and it was further purified by reverse phase high performance liquid chromatography. To identify the covalently bound azodipyrrole amino acid residue in albumin, the azodipyrrole-albumin conjugate was cleaved to fragmented peptides by chemical and enzymatical methods, and three main peptide fractions which had the absorption characteristics of azodipyrrole at 530 nm were isolated. Their amino acid sequence analysis revealed that all of the peptides corresponded to residues 187–191 in albumin, where lysine residue 190 was identified as the covalent-binding site of albumin to bilirubin in δ bilirubin.

We previously reported that sulfobromophthalein infusion inhibited the biliary excretion of estradiol glucuronides, whereas dibromosulfophthalein had no effect. In the present study, we examined the biliary excretion of estrone metabolites in rats. Biliary excretion of a tracer dose of intravenously injected [³H]estrone to control rats or EHBR and effects of the infusion of sulfobromophthalein and dibromosulfophthalein were studied. Biliary excretion of estrone metabolites was delayed in EHBR. Analysis of the biliary estrone metabolites revealed a marked decrease of the glucuronides in EHBR. Sulfobromophthalein and dibromosulfophthalein infusion (0.2 μmol/min/100 g b.wt.) inhibited the biliary excretion of estrone metabolites. However, the decrease in biliary excretion of the glucuronides was observed only with sulfobromophthalein that is excreted mainly as the glutathione conjugate. These findings indicate that glucuronides of estrone and its metabolites are partly excreted into bile by a canalicular organic anion carrier for sulfobromophthalein-glutathione, but not for dibromosulfophthalein.

Evolving knowledge on autoimmune hepatitis (AH) since the 1950s has highlighted its challenge to nosology. Descriptive diagnostic criteria have been provided recently from three sources: (i) the IASL revision of the 1976 Fogarty manual; (ii) the World Congress of Gastroenterology Terminology Working Party; (iii) the International Autoimmune Hepatitis Group (Brighton Report). Problems with definition of AH relate to (i) stage of disease, whether very early or very late, when markers are less evident; (ii) distinction between an ‘autoimmune state’ with minimal disease (‘chronic persistent hepatitis’) and progressive autoimmune hepatitis; (iii) overlaps and/or coexistences among autoimmune diseases affecting the liver or other tissues; (iv) possible subtypes, whether based on serological reactions or HLA $\text{DR3}\text{DR4}$ phenotypes. The particular problem presented by cases of HCV-associated chronic hepatitis with LKM autoantibodies is unresolved, but such cases are best placed in a virological category. There is a call for standardisation of testing and uniformity in expression of results for autoantibodies relevant to AH. The diagnostic utility of antibody to asialoglycoprotein receptor is promising despite difficulty in production, and insufficient sensitivity and specificity of current assays. Meanwhile the serological diagnosis of AH is necessarily based on carefully titrated reactivity by immunofluorescence for antibodies to nuclei or actin (Type 1), or liver-kidney microsomes (Type 2).

The expression of TGF-β receptor types I, II and III in freshly-isolated and monolayer cultured rat hepatocytes was studied at the RNA and protein level applying semiquantitative RT-PCR and immunocytochemistry (APAAP-, and fluorescence-staining, respectively). Transcripts of receptor types I, II and III were detected in cultured cells, the level of mRNA for the type I and type II receptors were present at each time point of culture and showed no change of expression during cultivation. The transcript of TGF-β type III receptor (betaglycan) was very sparse in freshly-isolated cells but showed a 5–6-fold increase up to 72 h of culture. Southern blotting and enzymatic cleavage of the PCR-amplificates proved the specificity of the PCR products. Immunochemical staining of cultured PC (48 h) with polyclonal anti-type I, -type II and -type III TGF-β receptor antibodies demonstrated the presence of the receptors with almost similar staining intensities. In freshly isolated PC staining for type III receptor was weakly. The results indicate a differential expression of TGF-β signaling receptors (I and II) and betaglycan co-receptor (III), respectively, in cultured PC.