Oxidative stress in toxicology: established mammalian and emerging piscine model systems.

Abstract

Interest in the toxicological aspects of oxidative stress has grown in recent years, and research has become increasingly focused on the mechanistic aspects of oxidative damage and cellular responses in biological systems. Toxic consequences of oxidative stress at the subcellular level include lipid peroxidation and oxidative damage to DNA and proteins. These effects are often used as end points in the study of oxidative stress. Typically, mammalian species have been used as models to study oxidative stress and to elucidate the mechanisms underlying cellular damage and response, largely because of the interest in human health issues surrounding oxidative stress. However, it is becoming apparent that oxidative stress also affects aquatic organisms exposed to environmental pollutants. Research in fish has demonstrated that mammalian and piscine systems exhibit similar toxicological and adaptive responses to oxidative stress. This suggests that piscine models, in addition to traditional mammalian models, may be useful for further understanding the mechanisms underlying the oxidative stress response.ImagesFigure 1Figure 2Figure 3

Assessment of biomarkers for contaminants of emerging concern on aquatic organisms downstream of a municipal wastewater discharge

“…An increased GSSG-to-TGSH ratio is considered indicative of oxidative stress; it is the result of the conversion of glutathione from reduced to oxidized form as radicals with oxidative potential are neutralized (Kelly et al, 1998). The mean GSSG to TGSH ratios in the livers of the fish caged at the most impacted sites (i.e.…”

Generation of reactive oxygen species in relevant cell lines as a bio-indicator of oxidative effects caused by acid mine water

“…Aquatic pollutants have potential to induce formation of ROS in organisms resulting in OS (Lesser, 2006) that can lead to cellular dysfunction and possibly death. The presence of transition redox-active transition metals can initiate a reaction to produce a highly reactive oxygen species (ROS), the hydroxyl radical (OH -), via the Fenton reaction (Kelly et al, 1998). The use of in-vitro contaminant-stimulated ROS production has been demonstrated in a number of species for a number of contaminants (Livingstone, 2001).…”

“…Metals such as Fe, Cu, Cr and V are redox active metals that generate ROS by redox cycling through enhancing production of oxyradicals within cells (Kelly et al, 1998). Transition metals like Fe 2+ can react with H 2 O 2 , with the net reaction leading to formation of a hydroxyl anion and radical (Sevcikova et al, 2011).…”

“…ROS formation initiated by the presence of contaminants, resulting in OS, has been reported in biota exposed to pollutants. This suggests a possible connection between contaminantstimulated ROS production and resultant OS as an established pathway of toxicity in exposed organisms which is present in aquatic animals to prevent ROS-induced damage (Di Giulio et al, 1995;Kelly et al, 1998;Winston and Di Giulio, 1991). Sustained increase in ROS generation (OH-radicals, hydrogen peroxide, and superoxide anions) leads to OS, causing distress in cellular metabolism and regulation, membrane and organelle damage and/or cellular death (Kelly et al, 1998).…”

Arbuscular Mycorrhizal Fungi Alleviate the Negative Effects of Iron Oxide Nanoparticles on Bacterial Community in Rhizospheric Soils

“…(Auffan et al, 2008). The ROS production and resulting oxidant stress for microbes may cause cell apoptosis by damaging cellular lipids, carbohydrates, proteins and DNA (Kelly et al, 1998;Kahru et al, 2008). For example, Auffan et al (2008) Figure 2).…”