Oxidative stress and arsenic toxicity: Role of NADPH oxidases

• Published in: Chemosphere (Oxford) 2013-02, Vol.90 (6), p.1987-1996
• Main Authors: Gupta, D.K., Inouhe, M., Rodríguez-Serrano, M., Romero-Puertas, M.C., Sandalio, L.M.
• Format: Article
• Language: English
• Subjects: (S)-2-hydroxy-acid oxidase; Antioxidants; Arabidopsis; Arabidopsis - metabolism; Arabidopsis thaliana; Arsenic; Arsenic - toxicity; Biological and medical sciences; catalase; Catalase - metabolism; copper; Environmental Pollutants - toxicity; Fundamental and applied biological sciences. Psychology; Glutathione Reductase - metabolism; glutathione-disulfide reductase; hydrogen peroxide; Hydrogen Peroxide - metabolism; iron; malondialdehyde; Malondialdehyde - metabolism; mutants; NADPH oxidase; NADPH Oxidases - metabolism; nitric oxide; Non agrochemicals pollutants; Nutrients; Oxidative Stress; Phytopathology. Animal pests. Plant and forest protection; Pollution effects and side effects of agrochemicals on crop plants and forest trees. Other anthropogenic factors; Pollution effects. Side effects of agrochemicals; Reactive oxygen species (ROS); superoxide dismutase; Superoxide Dismutase - metabolism; toxicity; zinc
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2012.10.066

► Arsenic induces oxidative stress by over-accumulation of ROS and reduction of NO. ► NADPH oxidase C is not the main source of ROS under As toxicity. ► NADPH oxidase C regulates directly or indirectly the nutrient uptake. ► Glycolate oxidase could be the main source of ROS induced by As. The effect of arsenic (25 and 50μM As for 1 and 5d) was analysed in wild type (WT) and Arabidopsis thaliana (L.) Heynh plants deficient in NADPH oxidase C (AtrbohC). The content of H2O2 and malondialdehyde (MDA) increased with the As concentration, while the opposite effect was found for NO in WT and AtrbohC plants. The As treatment reduced catalase and increased glutathione reductase activities to the same extent in WT and AtrbohC plants, although the induction of all SOD isoforms (mainly CuZn–SODs) was observed in WT plants, the opposite effects being found in AtrbohC plants. Glycolate oxidase (H2O2 producers) considerably increased with the concentration and time of treatment with As in WT and AtrbohC mutants. Arsenic induced the uptake and translocation of P, S, Cu, Zn, and Fe in WT plants, while in AtrbohC plants the opposite trend was noted and the uptake of As became considerably lower than in WT plants. These results suggest that As causes oxidative stress by inducing glycolate oxidase, while NADPH oxidase does not appear to participate in ROS overproduction but could be critical in regulating antioxidant defences as well as the transport and translocation of As and macro/micronutrients.