Comparison of oxidative stress induced by inorganic arsenic and dimethylmonothioarsinic acid in HaCaT cells

• 1、School of Public Health, Soochow University, Soochow 215123

Abstract：[Object] The difference in oxidative stress induced by arsenic methylation metabolite dimethylmonothioarsinic acid (DMMTA) and inorganic arsenic was compared in human keratinocytes (HaCaT). It is to provide basic information for the toxicity assessment of arsenic methylation metabolites and the study of carcinogenic mechanisms. [Methods] Human keratinocytes were randomly divided into 7 groups. The cells were treated with normal medium (control group) and medium containing 0.5μM sodium arsenite, 1.0μM sodium arsenite, 5.0μM sodium arsenite, 0.5μM DMMTA, 1.0μM DMMTA, 5.0μM DMMTA for 24 hours, respectively. The levels of malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), hydrogen peroxide, superoxide and glutathione in human keratinocytes were measured with the suitable kit. [Results] At the same dose, the levels of oxidative damage (MDA, 8-OHdG) in the DMMTA treatment group were significantly higher than those in the inorganic arsenic treatment group (P<0.05) and the levels of reactive oxygen species (hydrogen peroxide, superoxide) were also significantly higher than those in the inorganic arsenic treatment group (P<0.05), while the levels of glutathione were significantly lower than those in the inorganic arsenic treatment group (P<0.05). [Conclusion] At the same dose, compared with the inorganic arsenic, DMMTA is more likely to cause oxidative damage in HaCaT cells .This is not only because it is more readily to stimulate the production of reactive oxygen species, but also because it consumes intracellular antioxidants (glutathione) specially.

Keywords： arsenic sodium arsenite dimethylmonothioarsinic acid human keratinocyte oxidative stress