Effect Of Arsenic Trioxide On Antioxidant Abilities And Proliferative Activities Of Marrow Cells In Rats

Arsenic, which is a highly poisonous metalloid, causes acute and chronic adverse health effects, including skin lesions, hyperkeratosis, blackfoot disease and cancer. The exact mechanism of the action of arsenical toxicity is not known clearly, but several hypotheses have been proposed. Oxidative stress, altered cell proliferation, genotoxicity including altered DNA methylation, co-carcinogenesis, and tumor promotion are the potential mechanisms, as described previously. Oxidative damage has been found to play an important role in the arsenic-induced toxicity and carcinogenicity of many organisms. Recently, organic arsenic has been widely used in livestocks production, and arsenic trioxide has been successfully employed in the treatments of the majority of cases of acute promyelocytic leukemia (APL). A better understanding of the action of arsenic on marrow cells will make a more confident assessment of the risks associated with arsenical therapy and arsenical exposure. With the purpose of preventing drug abuse and protecting human health, we observed the effect of As₂O₃ on antioxidant abilities and proliferative activities of marrow cells in vivo and vitro.In the first experiment, fifty rats were separated randomly into five groups of ten rats each, and were respectively administered via ig the water containing arsenic (0, 5, 20, 80 and 320 mg/L) for three months. Then the antioxidant abilities of marrow cells, hemanalysis parameters of peripheral blood and viscera coefficients of organs were analyzed after rats were killed. In the second experiment, marrow cells were collected from healthy rats to determine the effect of arsenic on proliferative abilities of marrow cells by MTT method.The results of the first experiment were as follows: (1) Compared with the control group, the activities of GSH-Px and SOD as well as the content of GSH in rat marrow cells increased remarkably in 20, 80 and 320 mg/L As₂O₃ groups (P<0.01); but the activity of GSH-Px decreased significantly in 5 mg/L As₂O₃ group (P<0.01). The activity of SOD and the content of GSH in 5 mg/L As₂O₃ group did not differ from the control group. The content of MDA in rat marrow cells from arsenic treated group was significantly higher than that of the control group (P<0.01). The levels of ROS and anti-superoxide anion radical in rat marrow cells from 5 mg/L As₂O₃ group were higher...