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Differential responses to copper-induced oxidative stress in the marine macroalgae Lessonia nigrescens and Scytosiphon lomentaria (Phaeophyceae).
Aquat Toxicol. 2009 Aug 31; 94(2):94-102.AT

Abstract

In order to help explain the absence of the brown kelp Lessonia nigrescens from a coastal environment chronically enriched with copper, we characterized the biochemical responses induced by copper stress in this kelp and compared them with those displayed by the copper tolerant brown alga Scytosiphon lomentaria. These algae were cultivated with increasing concentrations of copper (20, 40 and 100microgL(-1)) for 96h and the temporal production of hydrogen peroxide, superoxide anions and lipoperoxides as well as the activities of antioxidant enzymes catalase (CAT), glutathione peroxidase (GP), ascorbate peroxidase (AP), dehydroascorbate reductase (DHAR) and glutathione reductase (GR) and the activity of the defense enzyme lipoxygenase (LOX) were determined. In L. nigrescens and S. lomentaria, a single peak of hydrogen peroxide was detected, with similar maxima after 3h of copper exposure, although in L. nigrescens buffering took longer. Superoxide anions, on the other hand, were only detected in L. nigrescens. The production of lipoperoxides in L. nigrescens increased steadily at higher copper levels, in a pattern clearly different to their rapid stabilization in S. lomentaria. We suggest that the accumulation of lipoperoxides might be related to LOX, whose activity also increases with exposure time. Furthermore, activities of the antioxidant enzymes CAT, GP, AP and DHAR were lower in L. nigrescens than in S. lomentaria, and GP and DHAR were completely inhibited at higher copper concentrations. Since these enzymes also detoxify fatty acid hydroperoxides, their inhibition, together with the activation of LOX, may explain the persistent and copper-dependent levels of lipoperoxides in L. nigrescens. Based on terrestrial plant models demonstrating toxic effects of lipoperoxides, and on our results on organellar ultrastructural changes, we suggest that copper toxicity induced an uncontrolled lipoperoxide accumulation which may lead to cell damage and dysfunction in L. nigrescens, explaining at least partially, the absence of this kelp in a copper-enriched coastal environment.

Authors+Show Affiliations

Departamento de Ecología, Center for Advanced Studies in Ecology and Biodiversity, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Postal Code 6513677, Santiago, Chile.No affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Comparative Study
Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

19581008

Citation

Contreras, Loretto, et al. "Differential Responses to Copper-induced Oxidative Stress in the Marine Macroalgae Lessonia Nigrescens and Scytosiphon Lomentaria (Phaeophyceae)." Aquatic Toxicology (Amsterdam, Netherlands), vol. 94, no. 2, 2009, pp. 94-102.
Contreras L, Mella D, Moenne A, et al. Differential responses to copper-induced oxidative stress in the marine macroalgae Lessonia nigrescens and Scytosiphon lomentaria (Phaeophyceae). Aquat Toxicol. 2009;94(2):94-102.
Contreras, L., Mella, D., Moenne, A., & Correa, J. A. (2009). Differential responses to copper-induced oxidative stress in the marine macroalgae Lessonia nigrescens and Scytosiphon lomentaria (Phaeophyceae). Aquatic Toxicology (Amsterdam, Netherlands), 94(2), 94-102. https://doi.org/10.1016/j.aquatox.2009.06.004
Contreras L, et al. Differential Responses to Copper-induced Oxidative Stress in the Marine Macroalgae Lessonia Nigrescens and Scytosiphon Lomentaria (Phaeophyceae). Aquat Toxicol. 2009 Aug 31;94(2):94-102. PubMed PMID: 19581008.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Differential responses to copper-induced oxidative stress in the marine macroalgae Lessonia nigrescens and Scytosiphon lomentaria (Phaeophyceae). AU - Contreras,Loretto, AU - Mella,Daniella, AU - Moenne,Alejandra, AU - Correa,Juan A, Y1 - 2009/06/13/ PY - 2009/04/22/received PY - 2009/06/03/revised PY - 2009/06/04/accepted PY - 2009/7/8/entrez PY - 2009/7/8/pubmed PY - 2009/8/22/medline SP - 94 EP - 102 JF - Aquatic toxicology (Amsterdam, Netherlands) JO - Aquat Toxicol VL - 94 IS - 2 N2 - In order to help explain the absence of the brown kelp Lessonia nigrescens from a coastal environment chronically enriched with copper, we characterized the biochemical responses induced by copper stress in this kelp and compared them with those displayed by the copper tolerant brown alga Scytosiphon lomentaria. These algae were cultivated with increasing concentrations of copper (20, 40 and 100microgL(-1)) for 96h and the temporal production of hydrogen peroxide, superoxide anions and lipoperoxides as well as the activities of antioxidant enzymes catalase (CAT), glutathione peroxidase (GP), ascorbate peroxidase (AP), dehydroascorbate reductase (DHAR) and glutathione reductase (GR) and the activity of the defense enzyme lipoxygenase (LOX) were determined. In L. nigrescens and S. lomentaria, a single peak of hydrogen peroxide was detected, with similar maxima after 3h of copper exposure, although in L. nigrescens buffering took longer. Superoxide anions, on the other hand, were only detected in L. nigrescens. The production of lipoperoxides in L. nigrescens increased steadily at higher copper levels, in a pattern clearly different to their rapid stabilization in S. lomentaria. We suggest that the accumulation of lipoperoxides might be related to LOX, whose activity also increases with exposure time. Furthermore, activities of the antioxidant enzymes CAT, GP, AP and DHAR were lower in L. nigrescens than in S. lomentaria, and GP and DHAR were completely inhibited at higher copper concentrations. Since these enzymes also detoxify fatty acid hydroperoxides, their inhibition, together with the activation of LOX, may explain the persistent and copper-dependent levels of lipoperoxides in L. nigrescens. Based on terrestrial plant models demonstrating toxic effects of lipoperoxides, and on our results on organellar ultrastructural changes, we suggest that copper toxicity induced an uncontrolled lipoperoxide accumulation which may lead to cell damage and dysfunction in L. nigrescens, explaining at least partially, the absence of this kelp in a copper-enriched coastal environment. SN - 1879-1514 UR - https://www.unboundmedicine.com/medline/citation/19581008/Differential_responses_to_copper_induced_oxidative_stress_in_the_marine_macroalgae_Lessonia_nigrescens_and_Scytosiphon_lomentaria__Phaeophyceae__ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0166-445X(09)00202-1 DB - PRIME DP - Unbound Medicine ER -