title: Effects of subchronic manganese chloride exposure on tambaqui (Colossoma macropomum) tissues: oxidative stress and antioxidant defenses.
abstract: This study aimed to evaluate oxidative stress parameters in juvenile tambaqui (Colossoma macropomum) exposed to 3.88 mg l(-1) Mn(2+) for 96 hours. Biomarkers of oxidative stress, such as thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), catalase (CAT), and glutathione-S-transferase (GST) activities, as well as content of reduced glutathione (GSH), were analyzed in gill, liver, brain, and kidney. The presence of Mn(2+) in the water corresponded to increased levels of Mn(2+) accumulation according to the following sequence: gill > kidney > brain > liver. There was a significant increase in TBARS levels (40 %) and SOD activity (80 %) in addition to a significant decrease in GSH content (41 %) in gills of fish exposed to waterborne Mn(2+). In hepatic tissue of the exposed animals, TBARS levels decreased significantly (35 %), whereas SOD (82 %) and GST activities (51 %) as well as GSH content (43 %) increased significantly. In brain of exposed juvenile fish, only significant decreases in SOD (32 %) and CAT activities (65 %) were observed. Moreover, the kidney of exposed fish showed a significant increase in TBARS levels (53 %) and a significant decrease in SOD activity (41 %) compared with the control. Thus, the changes in biomarkers of oxidative stress were different in the tissues, showing a specific toxicity of this metal to each organ.
authors: Department of Physiology and Pharmacology, Federal University of Santa Maria, Santa Maria-RS, Brazil.
authors: Diogo
authors: D
authors: Gabriel
authors: Ana Paula K
authors: AP
authors: Riffel
authors: Isabela A
authors: IA
authors: Finamor
authors: Etiane M H
authors: EM
authors: Saccol
authors: Giovana M
authors: GM
authors: Ourique
authors: Luis O
authors: LO
authors: Goulart
authors: Daiani
authors: D
authors: Kochhann
authors: Mauro A
authors: MA
authors: Cunha
authors: Luciano O
authors: LO
authors: Garcia
authors: Maria A
authors: MA
authors: Pavanato
authors: Adalberto L
authors: AL
authors: Val
authors: Bernardo
authors: B
authors: Baldisserotto
authors: Susana F
authors: SF
authors: Llesuy
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D060125:Characiformes / Q000502:physiology*; D002712:Chlorides / Q000633:toxicity*; D005880:Gills / Q000187:drug effects / Q000378:metabolism; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D008018:Life Cycle Stages / Q000187:drug effects / Q000502:physiology; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D017895:Manganese Compounds; D018384:Oxidative Stress / Q000187:drug effects*; D010088:Oxidoreductases / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D018675:Toxicity Tests; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D015415:Biomarkers; D002712:Chlorides; D017895:Manganese Compounds; D017392:Thiobarbituric Acid Reactive Substances; D014874:Water Pollutants, Chemical; D010088:Oxidoreductases; C025340:manganese chloride