The effects of pyriproxyfen on oxidative stress, protein carbonylation and reproductive endocrine disruption in Cyprinus carpio

In this study, we investigated the effects of insect growth regulator pyriproxyfen in liver, brain, kidney, gill and muscle tissues of Cyprinus carpio exposed to 0.0225 and 0.0450 ppm sublethal concentration of pyriproxyfen for 1, 4 and 7 days, then fish were left to depurate for 7 days in pesticide free water. Glutathione (GSH), malondialdehyde (MDA), protein carbonyl (PCO), estradiol, testosterone, hemoglobin (Hgb) and hematocrit (Hct) levels, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in blood were determined. Glutathione level increased in brain, liver and kidney tissues by the effects of 0.0225 and 0.0450 ppm pyriproxyfen at all period. It decreased on 7 day after 0.0225 ppm, on depuration period after 0.0450 ppm in gill, on 4 day after both treatments in muscle. Malondialdehyde level increased in brain, liver, kidney, gill and muscle tissues. After depuration period, MDA level were found higher than control level by the effects of 0.0450 ppm for all tissues. Protein carbonylation increased in brain, liver, kidney and gill tissues while it decreased in muscle tissue. After depuration period PCO level increased after 0.0225 ppm for all tissues except muscle. Estradiol and testosterone levels decreased after both treatments at all period while testosterone level was found at control level after 0.0225 ppm on depuration period. . Hemoglobin and Hct levels as well as AST activity decreased after both treatments at all period and depuration. Alanine aminotransferase activity increased on 4 day while it decreased other period.Results of this study showed that pyriproxyfen caused oxidative stress and an oxidative tissue damage was occured because of inadequate antioxidant defense system. The decreasing levels of estradiol and testosterone show pesticide mediated endocrine disruption. The result of this study also showed that it needs a longer duration than 7 days to depurate pesticide toxicity in fish.