Hepatic oval cells activated by hepatocyte apoptosis in diethylnitrosamine-induced rat liver cirrhosis.

OBJECTIVE: To investigate whether hepatic oval cells are activated in diethylnitrosamine (DEN)-induced rat liver cirrhosis, and to explore its mechanism. METHODS: Liver cirrhosis was induced in rats (n=8) by weekly intraperitoneal injections of DEN at a dose of 50mg/kg body weight for 12 weeks followed by a 2-week wash out period. Rats (n=5) that received isovolumic vehicle served as the control group. Liver pathology was examined. Apoptotic hepatocytes were identified and quantified by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) assay. Oval cells were detected using immunohistochemical staining for pyruvate kinase type M2 (M2PK) and cytokeratin 19 (CK19). The work was carried out at Renmin Hospital of Wuhan University, Wuhan, Hubei, China from February to December 2009. RESULTS: Liver cirrhosis developed in rats subjected to DEN administration. The TUNEL and morphology assay showed that a substantial number of hepatocytes underwent apoptosis. The apoptotic index in rats subjected to DEN administration (0.75 0.15) was much higher than normal control rats (0.10 0.05). Both CK19 and M2PK were moderately expressed in the rat liver cirrhosis, and the expression was dispersed or forming small cords in the liver; but the expression was hardly detected in the liver tissue of normal control rats. CONCLUSION: In the DEN-induced rat liver cirrhosis, oval cells are activated and stimulated to proliferation, the mechanism of which may be related to substantial hepatocyte apoptosis in the model.

No relationship between IL-1B gene polymorphism and gastric acid secretion in younger healthy volunteers.

AIM: To investigate the influence of IL-1B-511 gene polymorphism on IL-1B mRNA expression and gastric acid output in individual with or without Helicobacter pylori (H pylori) infection. METHODS: IL-1B mRNA expression and gastric acid secretion in 117 health volunteers were assayed using semi-quantitative RT-PCR and gastric juice assay, respectively. Pepsinogen (PG) I and II of 255 subjects (including 117 health volunteers) were also examined. RESULTS: T/T genotype individuals with H pylori infection had a more decreased PG I/II ratio. In gastric antrum mucosa, the individuals with H pylori infection had higher IL-1B expression than those without H pylori infection, but there was no obvious difference among each genotype. In gastric corpus, the individuals with H pylori infection had a significantly higher IL-1B expression than those without H pylori infection. IL-1B-511T/T genotype was markedly higher as compared with the other two genotypes. Both maximal acid output and basic acid output were similar among each genotype in IL-1B-511 gene locus, regardless of H pylori infection. CONCLUSION: IL-1B-511 T allele does not decrease gastric acid output, although it has a stimulated influence on IL-1B expression. Consequently, the pathway, through which IL-1B plays a central role in gastric cancer development, might not depend on low acid, but on the other regulation mechanisms.