title: 17β estradiol induced ROS generation, DNA damage and enzymatic responses in the hepatic tissue of Japanese sea bass.
abstract: The importance of endocrine disrupting chemicals and their effects on fish has been documented in recent years. However, little is known about whether the estrogenic compound 17β estradiol (E2) causes oxidative stress in the hepatic tissue of fish. Therefore, this work tested the hypothesis that E2 might cause oxidative stress in the Japanese sea bass Lateolabrax japonicus liver. To test this hypothesis, its effects on reactive oxygen species (ROS) production, DNA damage, antioxidants and biotransformation enzyme were investigated in two different size groups (fingerling and juvenile groups) following 30 days exposure. Results showed that there was a good relationship between the E2 exposure concentration, plasma E2 level and ROS generation. In addition ROS production correlated negatively with 7-ethoxyresorufin-O-deethylase activity and positively with DNA damage and lipid peroxidation (LPO). Antioxidant enzymes such as superoxide dismutase and catalase did not show any significant relation with ROS, LPO and DNA damage. In contrast, glutathione mediated enzymes showed a good relationship with the above parameters suggesting that the glutathione system in fish might be responsible for protection against the impact of E2 and also indicating a possible adaptive response during exposure periods. In addition, it was observed that fingerling was more susceptible to E2 exposure than juvenile fish. The present study provided strong evidence that the ROS level increased significantly in the liver of E2 exposed fish, and that ROS might serve as a biomarker to indicate estrogen contamination.
authors.affiliation: State Key Laboratory of Marine Environmental Science, College of Oceanography and Environmental Science, Xiamen University, Xiamen, Fujian, 361005, People's Republic of China.
authors.forename: Harikrishnan
authors.initials: H
authors.lastname: Thilagam
authors.forename: Singaram
authors.initials: S
authors.lastname: Gopalakrishnan
authors.forename: Hai-Dong
authors.initials: HD
authors.lastname: Qu
authors.forename: Jun
authors.initials: J
authors.lastname: Bo
authors.forename: Ke-Jian
authors.initials: KJ
authors.lastname: Wang
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001492:Bass / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D004249:DNA Damage; D052244:Endocrine Disruptors / Q000633:toxicity*; D004958:Estradiol / Q000633:toxicity*; D005978:Glutathione / Q000378:metabolism; D015227:Lipid Peroxidation; D008099:Liver / Q000201:enzymology / Q000503:physiopathology; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D052244:Endocrine Disruptors; D017382:Reactive Oxygen Species; D004958:Estradiol; D019363:Cytochrome P-450 CYP1A1; D013482:Superoxide Dismutase; D005978:Glutathione