ABSTRACT
BACKGROUND: Calpain, a cytosolic Ca(2+)-dependent proteinase, plays a pivotal role in cell injury. In this study, we investigated the effect of calpain-mu antisense oligonucleotide on oxidative stress induced-hepatocyte injury. MATERIALS AND METHODS: Hemagglutinating virus of Japan liposome complex with one of three types of antisense oligonucleotide (AS-1, AS-2, AS-3) or scramble oligonucleotide was added to the culture medium of HuH7 cells and incubated for 6 days. The expression of calpain-mu protein was examined by Western blotting. After the addition of tert-butyl hydroperoxide, bleb formation was examined by phase contrast microscopy, and cell viability was assessed by the release of lactate dehydrogenase. RESULTS: Incubation of HuH7 cells with AS-2 resulted in a decrease in the amount of calpain on day 4 and a further decrease to almost undetectable levels on day 6, whereas scramble oligonucleotide had no effect. Bleb formation was observed 120 min after the addition of tert-butyl hydroperoxide in scramble oligonucleotide-treated cells as in untreated cells. In contrast, it was rarely observed in AS-2-treated cells. Lactate dehydrogenase release was significantly suppressed in AS-2-treated cells, compared with that in scramble oligonucleotide treated-cells. CONCLUSIONS: Our findings suggest that calpain activation is involved in the pathogenesis of oxidative stress injury and that transfection of calpain antisense may potentially protect against ischemia/reperfusion liver injury.
Subject(s)
Calpain/genetics , Hepatocytes/enzymology , Hepatocytes/ultrastructure , Oligonucleotides, Antisense/genetics , Oxidative Stress , tert-Butylhydroperoxide/pharmacology , Calpain/physiology , Cell Survival/drug effects , Fluorescein-5-isothiocyanate , Fluorescent Dyes , Gene Expression , Hepatocytes/drug effects , Humans , L-Lactate Dehydrogenase/metabolism , Liver Neoplasms , Transfection , Tumor Cells, CulturedABSTRACT
Perforated duodenal ulcer was clinically evaluated with respect to Helicobacter pylori infection and rate of recurrence in 38 ulcer patients perforated and 154 patients with non-perforated duodenal ulcer who visited our hospital in past 5 years and 6 months. The frequency of occurrence of H. pylori-positivity was 42.1% in patients with perforated duodenal ulcer, significantly lower than that of 92.9% in patients with non-perforated lesions. This result suggests that H. pylori is hardly involved in the development of perforated duodenal ulcer. The rate of recurrence was significantly lower for perforated duodenal ulcer than for non-perforated ulcer. In particular, perforated duodenal ulcer did not recur in the group on maintenance therapy with H2-recepter antagonists. Maintenance therapy using inhibitors of gastric acid secretion seems effective for the prevention of recurrence of perforated duodenal ulcer.
