Induction of oxidative stress by arsenic in Clarias batrachus: involvement of peroxisomes.
Indian catfish, Clarias batrachus, were exposed to two nonlethal doses of arsenic for 10 days, which induced tissue lipid peroxidation, increased the ratio of oxidized to reduced glutathione and produced excess H(2)O(2) within 1-2 days of exposure. Furthermore, arsenic treatment increased the activity of antioxidant enzymes such as glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase but decreased glutathione reductase (GR) activity within a day of exposure, indicating the generation of oxidative stress in fish at an early stage. Reversibility of these arsenic-induced responses by pretreatment with N-acetylcysteine indicates that the oxidative stress was due to excess H(2)O(2) production, which was found to be partially contributed by altered H(2)O(2) metabolism in the peroxisomes. It is therefore concluded that peroxisomal H(2)O(2) metabolizing enzymes are potential targets of arsenic toxicity in C. batrachus.
Bhattacharya
Anirban
A
Environmental Toxicology Laboratory, Department of Zoology, Visva-Bharati University, Santiniketan 731235, West Bengal, India.
Bhattacharya
Shelley
S
D042962:Acyl-CoA Oxidase / Q000378:metabolism; D000818:Animals; D001151:Arsenic / Q000633:toxicity*; D000077237:Arsenic Trioxide; D001152:Arsenicals; D002374:Catalase / Q000378:metabolism; D002397:Catfishes / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D019803:Glutathione Disulfide / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D007928:Lethal Dose 50; D015227:Lipid Peroxidation; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism; D018384:Oxidative Stress; D010087:Oxides / Q000633:toxicity*; D020675:Peroxisomes / Q000187:drug effects* / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism
D001152:Arsenicals; D010087:Oxides; D006861:Hydrogen Peroxide; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D042962:Acyl-CoA Oxidase; D005980:Glutathione Reductase; D005978:Glutathione; D001151:Arsenic; D000077237:Arsenic Trioxide; D019803:Glutathione Disulfide