Lanthanum ions intervened in enzymatic production and elimination of reactive oxygen species in leaves of rice seedlings under cadmium stress.

Wang, Cheng‐Run; Wang, Qin‐Ying; Tian, Yuan; Zhang, Ji‐Feng; Li, Zhi‐Xiao; Cao, Peng; Zhu, Mei; Li, Ting‐Ting

Rare earth elements at proper concentrations were observed to alleviate heavy metal stress. However, the potential mechanisms of alleviation are not clear. Thus, the present study focused on the mechanisms of lanthanum (La) ions on the generation and elimination of reactive oxygen species (ROS) production in leaves of rice seedlings hydroponically cultivated in 30 µM cadmium chloride (CdCl2) for 2 d. Results showed that the decline of superoxide (O2 · −) or hydrogen peroxide (H2O2) was attributed not only to the decreased expressions of nicotinamide adenine dinucleotide phosphate oxidases-related gene, protein synthesis, and isozymes, but also to the decrease of xanthine oxidase, diamine oxidase, and guaiacol peroxidases isozymes and activities. Genes and isozymes related to superoxide dismutase, catalase, and ascorbate peroxidase were also differentially upregulated to control ROS accumulation when proper concentrations of La were combined with 30 µM Cd. Based on the results, one may conclude that La at proper concentrations not only limited the generation of O2 · − and H2O2 from the enzymatic sources but also promoted the elimination of O2 · − and H2O2 via the upregulating expressions of antioxidant enzyme-related genes and activities in the rice seedling's leaves under Cd stress. Environ Toxicol Chem 2014;33:1656-1664. © 2014 SETAC

OXYGEN in the body; LANTHANUM compounds; ENZYMATIC analysis; PHYSIOLOGICAL effects of cadmium; OXIDASES

Environmental Toxicology & Chemistry, 2014, Vol 33, Issue 7, p1656

0730-7268

Academic Journal

10.1002/etc.2610