Hepatic heme-oxygenase and oxidative stress during short-term treatment with DAB

GEREZ, ESTHER; CABALLERO, FABIANA; BATLLE, ALCIRA; VAZQUEZ, ELBA

Edinburgo, Inglaterra

Congreso; 76th Meeting Biochemical Society-Heriot-Watt University; 2002

The Biochemical Society, UK

Experimental hepatocarcinogenesis (HC) is a complete process involving multiple stage. We have proposed a probable mechanism for the onset of HC that includes a primary activating liver status which provokes biochemical aberrations leading to the initiation. The aim of this study has been to evaluate the HO behaviour and oxidative stress provoked during short-term treatment with the carcinogen p-paradimethylaminoazobenzene (DAB). CF1  mice weighing 25-30 g were fed with DAB during a whole period of 6 weeks. Animals were sacrificed once a week. The overall HO activity diminished since week 4 in DAB treated animals. TBARS content increased as soon as after the first week of treatment. The activities of the antioxidant enzymes, catalase and superoxide dismutase diminished from week 2, being markedly reduced at the end od the experiment (40% and 60%, respectively). GSH content increased gradually (40%) along the period assayed. Glutathione reductase activity was significantly increased from the first week. Otherwise glutathione peroxidase activity was not modified during the first three weeks and was slightly reduced in the last two weeks. These results add further support to our hypothesis that oxydative stress is implicated in the development of HC chemically induced and the involvement of possible cytoprotective role of HO