Oxidative stress parameters and antioxidant response to sublethal waterborne zinc in a euryhaline teleost Fundulus heteroclitus : protective effects of salinity

Date

2012

Authors

Journal Title

Journal ISSN

Volume Title

Publisher

Elsevier

Abstract

Zinc is an essential trace metal, but many aspects of its toxicity remain unclear. In this study, we investigated zinc effects on oxidative stress parameters and antioxidant profile in four tissues (gill, liver, kidney, and white muscle) of Fundulus heteroclitus. Possible interactive effects of salinity were also studied. Killifish were exposed to sublethal level (500 μgL(-1)) of waterborne zinc for 96 h in 0% (fresh water), 10% (3.5 ppt), 30% (10.5 ppt) and 100% sea water (35 ppt). Salinity per se had no effect on any parameter in the control groups. Zinc exposure clearly induced oxidative stress, and responses were qualitatively similar amongst different tissues. Salinity acted as a strong protective factor, with the highest levels of reactive oxygen species (ROS) and greatest damage (protein carbonyls, lipid peroxidation as indicated by thiobarbituric acid reactive substances (TBARS) in 0 ppt, the least in 100% sea water (35 ppt), and gradations in between in many of the observed responses. Increases in total oxidative scavenging capacity (TOSC) occurred at higher salinities, correlated with increases in the activities of superoxide dismutase (SOD) and glutathione-S-tranferase (GST), as well as in tissue glutathione (GSH) concentrations. However, TOSC was depleted in zinc-exposed fish at 0 ppt, accompanied by decreases in SOD, GST, GSH, and also catalase (CAT) activity. Our results confirm that sublethal waterborne zinc is an oxidative stressor in fish, and highlight the important protective role of higher salinities in ameliorating the oxidative stress associated with zinc toxicity in this model estuarine teleost.

Description

Keywords

METALS, ZINC, OXIDATIVE PARAMETERS, ANTIOXIDANTS, OXIDATIVE STRESS, SALINE WATER, GILLS, LIVER, KIDNEY

Citation

Loro, V.L., Jorge, M.B., Rios da Silva, K., & Wood, C.M. (2012). Oxidative stress parameters and antioxidant response to sublethal waterborne zinc in a euryhaline teleost Fundulus heteroclitus: Protective effects of salinity. Aquatic Toxicology, 110-111, 187-193.doi:10.1016/j.aquatox.2012.01.012

URI

http://hdl.handle.net/10625/51479

DOI

Collections

IDRC Research Results / Résultats de recherches du CRDI
2010-2019 / Années 2010-2019
Battling pollution in coastal areas / Lutter contre la pollution dans les zones côtières