Tissue levels of the antioxidant enzymes superoxide dismutase and catalase in fish Astyanax bimaculatus from the Una River Basin

Abstract

This paper seeks to identify the biomarker response to oxidative stress in Astyanax bimaculatus, a freshwater fish, collected from the Una River and its associated water bodies. The fish were collected using fishing nets at three different points on the river basin, namely Fazenda Piloto (FP), Ipiranga (IP) and Remédios (RM), during the period from December 2013 to March 2014. Physical and chemical analyses of the water at the sample locations indicate that IP and RM possibly have larger concentration of either natural or anthropic pollutants as compared to FP. FP can therefore be considered as the point less impacted by pollutants than other points. Hepatic activity of antioxidant stress enzymes, superoxide dismutase (SOD) and catalase (CAT), were measured in the specimens. The levels of SOD were reduced at RM while they were elevated in fish collected at IP. The CAT levels for the fish at RM and IP were about 148.9% and 202.4% above the values at FP, respectively. These results suggest that antioxidant enzymes could be used as biomarkers to measure oxidative stress caused by pollutants in the Una River Basin.

Enzymes from kidney, gill and brain tissues of Astyanax bimaculatus (lambari) as biomarkers of environmental impact in the Una River basin

“…The present study showed that specimens from the P2 site had lower levels of renal SOD, while lower levels of this enzyme occurred in gills in fish from P3. Batista et al (2014) showed that the activity of hepatic SOD was higher in fish from P3, in comparison with that of P2. Therefore, SOD from liver, kidney or gills of A. bimaculatus could be used as a biomarker.…”

“…These results indicate that only SOD was sensible to environmental conditions present in P2. The physicochemical analysis of the water of sites P1, P2 and P3 at the time of fish capture has already been published, as well as the map with the location of these sites (Batista et al, 2014, Ribeiro et al, 2015. These data from the physicochemical analyses indicated that: (1) the less impacted site was P1, although its total phosphate level (0.3 mg L -1 ) was slightly elevated in relation to reference values (0.1 mg L -1 ); (2) the conductivity of the P2 aquatic environment (198.7 S cm -1 ) was 1.9 times higher than in P1, and 1.6 times higher than in P3, showing that P2 fish were exposed to high levels of electrolytes from an impacted environment (CETESB, 2009); (3) P3 presented the highest values of chemical oxygen demand (COD), indicating abundance of organic matter in the water.…”

“…The fish collection sites were: (1) Fazenda Piloto (P1) in the Itaim stream located on the property of Fazenda Piloto (an experimental farm) of the University of Taubaté (S 23º01' 38.3" W 45º30'31.6"); (2) Remédios (P2), a stream which flows to the Una River, located along the Remédios municipal road (S 23°03'26.4" W 45°30'23.5"), close to rice cultivation; (3) Ipiranga (P3), a lake near a pasture for cattle and close to the Dr. José Luiz Cembranelli municipal road (23º01'49.4" S and 45º30'16.7" W). The map of sampling sites was published in previous studies (Batista et al, 2014;Ribeiro et al, 2015). The specimen sampling was approved by MMA -SISBIO (authorization No.…”

“…The specimens of the fish Astyanax bimaculatus were collected at each of the three locations between December 2013 and March 2014. A size 20 nylon fishing net, as well as line and hook were used for collection as described by Batista et al (2014) and Ribeiro et al (2015). The fish were anesthetized with benzocaine 0.1%, dissected on an ice tray, and the tissues were stored at -86°C for further analysis.…”

“…The fish feeds on zooplankton, detritus, higher plants and sometimes fish scales, being an opportunistic feeder (Honorio and Martins, 2018). Levels of enzymatic activity of SOD and CAT of liver, and MDH and LDH of hepatic, muscular and branchial tissues of A. bimaculatus were previously investigated as candidate biomarkers of environmental changes in the Una River basin (Batista et al, 2014;Ribeiro et al, 2015;de Almeida et al, 2016). In this context, this work investigated the activity of SOD and CAT of renal and branchial tissues, MDH and LDH of renal and cerebral tissues, as well as brain AChE of A. bimaculatus.…”