Hematologic and hepatic responses of the freshwater fish Hoplias malabaricus after saxitoxin exposure

Abstract

The bioaccumulation of saxitoxins (STX) in the trophic chain, mainly in freshwater, are not completely known. This work aimed to elucidate the effects of STX on Hoplias malabaricus through trophic bioassay. The fish were fed once every five days with Astyanax sp. before being subjected to an intraperitoneal inoculation with the lysate of Cylindrospermopsis raciborskii culture containing 97% STX and 3% by neosaxitoxin and gonyautoxin during 20 days. The animal's liver was assessed using biomarkers as activities of superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), and glutathione peroxidase (GPx), and concentrations of reduced glutathione (GSH) and lipoperoxidation (LPO) and protein carbonylation (PCO). In the blood was analyzed the genotoxic and hematological parameters. The hepatosomatic index and the relative condition factor did not show a significant difference between the exposed and control groups. The values of mean corpuscular hemoglobin concentration and mean corpuscular hemoglobin increased in the STX group. The hepatic tissue from both groups exhibited a typical pattern that have been already described for most teleost fish. The results suggested the generation of reactive oxygen species, with increased activity of GPx and concentrations of LPO and GSH; whereas the specific activity of SOD decreased. However, no changes were observed in the CAT, PCO, and DNA damage. Although the STX effects are known as neurotoxic, this cyanotoxin caused liver biochemical alterations that can be considered ecologically relevant.

Effects of glyphosate on hepatic tissue evaluating melanomacrophages and erythrocytes responses in neotropical anuran Leptodactylus latinasus

“…Likewise, Brodkin et al (2007) exposed Rana pipiens to low concentrations of the herbicide atrazine there is an increase on phagocytic activity. Moreover, the increment in MMCs activity by GLY exposure could be associated with a detoxification, an oxidative damage of the liver and increasing the recruitment and activation of defense cells as mentioned some authors for fish (Sebrenski da Silva et al 2012;Mela et al 2013) and as potential indicator of overall fish health (Pacheco and Santos 2002;Agius and Roberts 2003;Pascoli et al 2011;Silva de Assis et al 2013). In particular, morphological changes in liver MMCs of anurans and an impaired immunological function, have been used as biomarkers for the effects of sewage effluents and Escherichia coli contamination (Franco-Belussi et al 2013); and temperature variations (Santos et al 2014).…”

Effects of trophic exposure to diclofenac and dexamethasone on hematological parameters and immune response in freshwater fish

“…Kumar and Xagoraraki [20] found a quantitative pharmaceutical risk after accidental contamination of stream water by fish consumption and direct ingestion of drinking water in children and adults [20]. Fish are particularly sensitive to water contamination and pollutants, including drugs for human and veterinary use, which may impair many physiological and immunological Immune response in fish exposed to anti-inflammatory drugs Environ Toxicol Chem 35, 2016 parameters [8]. In addition, fundamental immune molecules and mechanisms are similar in fish and mammals [21], and therefore, even though certain adverse effects have not yet been observed in humans, long-time exposure could affect our species in the future.…”

“…This fish species has the advantage that it is easily fed under laboratory conditions and has been explored in several trophic exposure biological studies [8,9]. This fish species has the advantage that it is easily fed under laboratory conditions and has been explored in several trophic exposure biological studies [8,9].…”

“…Hoplias malabaricus (Characiformes, Erythrinidae), a carnivorous fish with a large distribution in tropical rivers and lakes and consumed by many human populations, was used. This fish species has the advantage that it is easily fed under laboratory conditions and has been explored in several trophic exposure biological studies [8,9].…”

Effects of trophic exposure to dexamethasone and diclofenac in freshwater fish

“…The experimental model used in this study was Hoplias malabaricus (Characiformes, Erythrinidae), a carnivorous fish with large distribution in tropical rivers and lakes and very consumption by human populations (Ferreira et al, 2003). This fish has the advantage that it is easily fed under laboratory and has been explored in several biological studies (Monteiro et al, 2013;Silva de Assis et al, 2013).…”