No effective therapy has yet developed for liver fibrosis by directory inhibiting the accumulation of extracellular matrix. The effect of a newly synthesized prolyl4-hydroxylase (PH) inhibitor, HOE 077 (pyridine-2, 4-di-carboxylic-di(2-methoxyethyl)amide), was examined using the model of choline-deficient L-amino acid (CDAA) defined diet-induced liver fibrosis in 16-week-old male Wistar rats. HOE 077 at doses up to 200 ppm prevented fibrosis in a dose-dependent manner, as indicated by reduced hydroxyproline content in liver as well as inhibition of increased serum fibrotic markers (PIIIP, 7S, hyaluronic acid). HOE 077 at 200 ppm reduced expression of type III procollagen alpha 1, messenger RNA (mRNA) in the liver, with a good correlation with serum PIIIP and hydroxyproline content of the liver. Histologically, HOE 077 at 200 ppm also reduced proliferation of myofibroblastlike cells (activated Ito cells). These results indicate that a PH inhibitor can prevent fibrosis by inhibiting not only the hydroxylation of proline but also the activation of Ito cells, which are considered the main collagen-producing cells, resulting in reduced expression of procollagen mRNA.

A choline-deficient L-amino acid-defined (CDAA) diet led to the development of liver cirrhosis in 100% of male Wistar rats after 16 weeks. In contrast, an ordinary (semipurified) choline-deficient (CD) diet led to the development of liver cirrhosis in only 33.3%. After 16 weeks, the liver hydroxyproline content, which reflects the amount of collagen, increased to a level more than four times higher in rats fed a CDAA diet than in rats fed a choline-supplemented L-amino acid-defined (CSAA) diet. Concurrent administration of a prolyl 4-hydroxylase inhibitor, 2,4-pyridine dicarboxylic acid bis(2-methoxyethyl amide) (HOE 077), to rats fed a CDAA diet reduced this increase in liver hydroxyproline content in a dose-dependent manner for doses up to 200 p.p.m. Microscopically, reduction in the hydroxyproline content of the liver resulted in a reduced number of pseudolobuli and thinner fibrous septa. HOE 077 showed no effect on liver hydroxyproline content in rats fed a CSAA diet. The administration of a CDAA diet for 16 weeks led to a substantial induction of GSTP-positive lesions in the liver. The concurrent administration of HOE 077 reduced the number, average diameter and percent area of GSTP-positive lesions in a dose-dependent manner, in parallel with the reduction in hydroxyproline content. These data suggest that inhibition of fibrosis may limit the development of subsequent neoplasms.

Objective Early diagnosis of hepatocellular carcinoma (HCC) is critical in the management of patients with primary biliary cirrhosis (PBC), since the prognosis of PBC has improved. The aim of this study was to investigate whether HCC development affects the prognosis of PBC and to identify the risk factors for HCC in Japanese patients with PBC. Methods We compared the survival rates between patients with HCC and those without and analyzed the risk factors for HCC development in 210 patients with PBC who were followed up for a median period of 8.5 years. Results HCC developed during follow-up in 11 patients (5.2%) and was diagnosed simultaneously at the time of diagnosis of PBC in five patients (2.4%) who were excluded from the analysis. A Kaplan-Meier analysis showed a significant difference in overall survival between the patients who did and did not develop HCC (p<0.001). A multivariate analysis revealed age (OR: 1.08, 95% confidence interval [CI]: 1.03-1.13, p= 0.001), the albumin level (OR: 0.24, 95% CI: 0.10-0.56, p=0.001), the total bilirubin level (OR: 1.60, 95% CI: 1.09-2.36, p=0.017) and HCC development (OR: 2.97, 95% CI: 1.24-7.15, p=0.015) to be significant prognostic factors and identified only an advanced histological stage (Scheuer's classification III or IV, OR: 6.27, 95% CI: 1.80-21.83, p=0.004) to be a risk factor associated with HCC. Conclusion HCC development significantly affects the survival of patients with PBC, and an advanced histological stage is the only risk factor associated with HCC development. These results highlight the important role of liver fibrosis in hepatocarcinogenesis in patients with PBC.

ABSTRACT— This study evaluated whether liver regeneration could take place after massive or submassive necrosis of liver cells in 25 patients with several kinds of hepatic failure by immunohistochemical staining for proliferating cell nuclear antigen (PCNA). PCNA positivity was significantly higher (P<0.01) in the patients who survived than in the patients who died. Furthermore, PCNA‐positive hepatocytes were recognized diffusely in the lobule of the liver in survivors. There was positive correlation between PCNA positivity and plasma concentration of AFP (α‐fetoprotein), (r = 0.77, P<0.01). These results show that liver regeneration could take place after massive necrosis of liver cells in survivors from acute hepatic failure and that immunohistochemical staining for PCNA is useful for prognostic evaluation.

No effective therapy has yet developed for liver fibro-Among the different causes of liver cirrhosis, one sis by directory inhibiting the accumulation of extracel-common feature is an increased deposition of extracellular matrix. The effect of a newly synthesized prolyl lular matrix, which consists mainly of collagen, in the 4-hydroxylase (PH) inhibitor, HOE 077 (pyridine-2,4-di-liver, 1 leading to portal hypertension, esophageal varicarboxylic-di(2-methoxyethyl)amide), was examined us-ces, and liver failure. ing the model of choline-deficient L-amino acid (CDAA)A key enzyme in collagen synthesis is prolyl 4-hydefined diet-induced liver fibrosis in 16-week-old male droxylase, 2,3 which catalyzes the hydroxylation of pepWistar rats. HOE 077 at doses up to 200 ppm prevented tide-bound proline residues to 4-hydroxyproline. Hyfibrosis in a dose-dependent manner, as indicated by redrogen bonds, including those of hydroxyl groups, play duced hydroxyproline content in liver as well as inhibia crucial role in stabilizing the triple helix of collagetion of increased serum fibrotic markers (PIIIP, 7S, hyaluronic acid). HOE 077 at 200 ppm reduced expression of nous proteins. Newly synthesized procollagen motype III procollagen a 1 messenger RNA (mRNA) in the leclues that have not undergone hydroxylation are unliver, with a good correlation with serum PIIIP and hy-able to form a stable triple helix, resulting in their droxyproline content of the liver. Histologically, HOE rapid degradation at physiological temperature. Thus, 077 at 200 ppm also reduced proliferation of myofi-prolyl 4-hydroxylase is an excellent target enzyme in broblastlike cells (activated Ito cells). These results indi-efforts to prevent fibrogenesis. cate that a PH inhibitor can prevent fibrosis by inhib-The new prolyl 4-hydroxylase inhibitor, HOE 077 iting not only the hydroxylation of proline but also the (Hoechst Pharmaceutical Co., Frankfurt, Germany), is activation of Ito cells, which are considered the main a proinhibitor that is absorbed well from the gastroin- in hepatocytes to a competitive inhibitor of prolyl 4-hydroxylase. 4,5 In the present study, we induced the development of Liver cirrhosis is very common disease in Japan as liver cirrhosis in male Wistar rats by administering a well as in other countries and results from chronic hepcholine-deficient L-amino acid (CDAA) defined diet 6,7 atitis (type B or type C), ethanol abuse, or other condiinstead of a semipurified choline-deficient diet. 8,9 The tions. Interferon alfa and beta have been studied as replacement of protein with same equivalent of Lpossible therapeutic agents for the eradication of virus amino acids (a CDAA diet) had a more necrogenic effect in patients with chronic viral hepatitis resulting in the caused by a lack of oligopeptides and antioxidant minprevention of liver fibrosis. However, the results of erals resulting in more active fibrosis compared with these studies have been generally unsatisfactory.a semipurified choline-deficient (CD) diet. 7 Using this model, we inve...