Glutathione depletion in healthy cadmium-exposed Erica andevalensis

• Published in: Environmental and experimental botany Vol. 75; pp. 159 - 166
• Main Authors: Márquez-García, Belén, Horemans, Nele, Torronteras, Rafael, Córdoba, Francisco
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 2012; Elsevier
• Subjects: antioxidant activity; antioxidants; Ascorbate; ascorbate peroxidase; ascorbic acid; Biological and medical sciences; Cadmium; chlorophyll; Erica; Fundamental and applied biological sciences. Psychology; Glutathione; glutathione dehydrogenase (ascorbate); glutathione-disulfide reductase; Heavy metals; leaves; Lipid peroxidation; metal tolerance; microscopy; Oxidative stress; soil; superoxide dismutase; Iberian Peninsula; Lipid peroxidation; Cadmium; Oxidative stress; Ascorbate; Heavy metals; Glutathione; Plant ecology; Lipids; Woody plant; Heavy metal; Depletion; Dicotyledones; Angiospermae; Botany; Spermatophyta; Ericaceae; Erica; Peroxidation
• ISSN: 0098-8472; 1873-7307
• DOI: 10.1016/j.envexpbot.2011.09.009

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Erica andevalensis is a metal-tolerant heather from SW Iberian Peninsula. ► Cadmium is a highly toxic metal without known role in plant metabolism. ► In the presence of cadmium ascorbate is enhanced while glutathione is depleted. ► Microscopy analysis revealed that Cd is accumulated in the palisade mesophyll. ► No damage is reflected neither in pigments or lipid peroxidation levels.
The effects of cadmium (0.05–50
ppm in soils) on the antioxidant mechanisms of
Erica andevalensis have been investigated under laboratory-controlled conditions.
E. andevalensis, an endemic metal-tolerant species from SW Iberian Peninsula, is able to colonize extreme mine environments and to survive in very acid and metal enriched soils. Cadmium was taken up and accumulated in the leaves up to 0.5
ppm in plants watered with the highest concentration of this metal. The plants exposed to cadmium showed an increase in the levels of ascorbic acid and a decrease in the glutathione content. The activities of the antioxidative enzymes superoxide dismutase (SOD) and ascorbate peroxidase (APX) were enhanced whereas those of dehydroascorbate reductase (DHAR) and glutathione reductase (GR) were depleted in cadmium treated plants. Despite the fact that cadmium reached the leaves of the plant, and microscopy analysis revealed that mainly accumulated in the photosynthetic tissue, no significant changes were observed in the chlorophyll contents. Moreover, no damages were observed, neither visually, nor reflected in the lipid peroxidation, suggesting the great effectiveness of the mechanisms of this species to cope against metals.