Cadmium induces two waves of reactive oxygen species in Glycine max (L.) roots

• Published in: Plant, cell and environment cell and environment, 2014-07, Vol.37 (7), p.1672-1687
• Main Authors: PÉREZ‐CHACA, MARÍA VERÓNICA, RODRÍGUEZ‐SERRANO, MARÍA, MOLINA, ALICIA S, PEDRANZANI, HILDA E, ZIRULNIK, FANNY, SANDALIO, LUISA M, ROMERO‐PUERTAS, MARÍA C
• Format: Article
• Language: English
• Subjects: antioxidant enzymes; Antioxidants - metabolism; Ascorbic Acid - metabolism; Biological and medical sciences; cadmium; Cadmium - toxicity; dehydrogenases; enzymes; Fundamental and applied biological sciences. Psychology; Glutathione - analogs & derivatives; Glutathione - metabolism; Glycine max; Glycine max - drug effects; Glycine max - enzymology; Glycine max - metabolism; heavy metals; hydrogen peroxide; leaves; lipid peroxidation; Lipids - analysis; metabolism; NADP (coenzyme); NADP - metabolism; NADPH; nitric oxide; Nitric Oxide - metabolism; oxidative stress; Oxidative Stress - drug effects; oxygen; Plant Extracts - metabolism; Plant Leaves - drug effects; Plant Leaves - metabolism; Plant Proteins - metabolism; Plant Roots - drug effects; Plant Roots - metabolism; Reactive Oxygen Species - metabolism; roots; soybeans; xylem
• ISSN: 0140-7791; 1365-3040
• DOI: 10.1111/pce.12280

Cadmium (Cd) is a non‐essential heavy metal that may be toxic or even lethal to plants as it can be easily taken up by the roots and loaded into the xylem to the leaves. Using soybean roots (Glycine max L.) DM 4800, we have analysed various parameters related to reactive oxygen metabolism and nitric oxide (NO) during a 6 day Cd exposure. A rise in H₂O₂ and NO, and to a lesser extent O₂ ·⁻ content was observed after 6 h exposure with a concomitant increase in lipid peroxidation and carbonyl group content. Both oxidative markers were significantly reduced after 24 h. A second, higher wave of O₂ ·⁻ production was also observed after 72 h of exposure followed by a reduction until the end of the treatment. NOX and glicolate oxidase activity might be involved in the initial Cd‐induced reactive oxygen species (ROS) production and it appears that other sources may also participate. The analysis of antioxidative enzymes showed an increase in glutathione‐S‐transferase activity and in transcript levels and activity of enzymes involved in the ascorbate‐glutathione cycle and the NADPH‐generating enzymes. These results suggest that soybean is able to respond rapidly to oxidative stress imposed by Cd by improving the availability of NADPH necessary for the ascorbate‐glutathione cycle.