Cyanobacterium producing cylindrospermopsin cause oxidative stress at environmentally relevant concentrations in sub-chronically exposed tilapia (Oreochromis niloticus)

Influence of Two Depuration Periods on the Activity and Transcription of Antioxidant Enzymes in Tilapia Exposed to Repeated Doses of Cylindrospermopsin under Laboratory Conditions

“…Previous studies have reported that oxidative stress might play a role in the pathogenicity of CYN on tilapia exposed to a single dose [13,21] or repeated doses [23] of this molecule. However, the influence of different depuration periods on the changes in oxidative stress biomarkers induced by CYN has not been analyzed up to date.…”

“…In this sense, Guzmán-Guillén et al [23] showed an involvement of oxidative stress as a mechanism of toxic action of CYN in tilapia after sub-chronic exposure to cyanobacterial cells containing CYN (10 and 100 μg CYN/L), for 7 and 14 day by immersion route, mimicking natural exposure). It was demonstrated that subchronic exposure to low concentrations of cyanobacterial cells containing CYN exceeding 10 μg/L should be considered of particularly high risk for fish, because evident histopathological changes were found from this concentration [24].…”

Towards a physiological response of fishes under variable environmental conditions: An approach through neural network

“…The activation of oxidative manifestations leads to response of antioxidants, activation of genes encoding antioxidant enzymes and elevation in the concentration of ROS scavengers. Antioxidant enzyme activities can be used to detect early responses in fish to different xenobiotics and toxicants (Pavlović et al, 2010;Hellou et al, 2012;Guzmán-Guillén et al, 2013). There is little or scanty data regarding changes in liver and gill antioxidant enzyme activities after the exposure of fish to the toxic aquatic environment.…”

“…Anthropogenic eutrophication of water bodies associated with urbanization and agricultural and industrial development is the main factor contributing to increased toxic substances (Cazenave et al, 2006;Guzmán-Guillén et al, 2013). The production and persistence of toxic elements depends on the complex interaction of many environmental factors (sunlight, temperature, pH, dissolved oxygen, turbidity, turbulence) (Van Apeldoorn et al, 2007;Posch et al, 2012).…”

Antioxidative responses in zebrafish liver exposed to sublethal doses Aphanizomenon flos-aquae DC-1 aphantoxins

“…The major defense mechanisms against ROS and their toxic byproducts include the enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione S-transferase (GST), as well as the non-enzymatic systems of antioxidant molecules such as glutathione (GSH) (Melegari et al, 2012). Changes in the levels of these components in fish tissues are widely used as bioindicators of oxidative stress in ecological risk situations, and antioxidant levels can be used to detect early physiological responses in fish to different toxicants (Hellou et al, 2012;Guzmán-Guillén et al, 2013).…”