Abstract: BRL-3A cells were injured by different doses of hydrogen peroxide （H₂O₂） and the cell survival rate was assessed by methyl thiazolyl tetrazolium (MTT) assay to select the optimal concentration of H₂O₂. The BRL-3A cells were divided into normal control，H₂O₂-induced and thioredoxin （Trx） pre-treatment groups with different concentrations. The assay kits of malondialdehyde (MDA)，superoxide dismutase (SOD) and catalase (CAT) were used to detect the alterations of oxidative stress.Cell proliferation of BRL-3A was inhibited significantly by 1000 μmol/L H₂O₂ (P＜0.05). 2.5 μmol/L Trx had the protective effect on H₂O₂-induced injury of BRL-3A cells by significantly decreasing MDA contents which were induced by H₂O₂ and increasing the activities of SOD and CAT (P＜0.05), thus protecting liver cells.Trx had protective effects on BRL-3A cells induced by H₂O₂.The mechanism might be related to its antioxidant activity.

Key words: thioredoxin; hydrogen peroxide; injury; protection