title: The ameliorating effects of vitamin E on hepatic antioxidant system and xenobiotic-metabolizing enzymes in fenvalerate-exposed iodine-deficient rats.
abstract: This study investigated the effects of vitamin E (VE) on hepatic antioxidant system and drug-metabolizing enzymes in fenvalerate (FEN)-exposed iodine-deficient (ID) Wistar rats. ID was produced by perchlorate containing drinking water. VE was introduced by a loading dose of 100 mg/kg/d, i.g. for the first three days in the last week of feeding period; then with a single maintenance dose of 40 mg/kg on the 4th day. During last week, FEN groups (F) received 100 mg/kg/d, i.p. FEN. VE alone did not significantly affect thyroid hormones and antioxidant parameters; however, significantly increased total cytochrome P450 (38%) and cytochrome b5 levels (36%). In all ID groups, plasma thyroid-stimulating hormone (TSH) levels increased markedly, but remained at control level in vitamin E plus FEN receiving iodine-deficient group (IDVF) group. Glutathione peroxidase activity showed marked increases in F (19%) and FEN-exposed iodine-deficient group (IDF, 48%) groups. FEN treatment significantly increased total cytochrome P450 (28%) and thiobarbituric acid reactive substance levels (36%), as well as 7-ethoxyresorufin O-deethylase (120%), 7-penthoxyresorufin O-deethylase (139%) and glutathione S-transferase (15%) activities and decreased total glutathione concentrations (28%) versus control. Overall results suggest that vitamin E has ameliorating effects on the measured parameters in ID and/or FEN exposure.
authors.affiliation: a Department of Toxicology , Faculty of Pharmacy, Hacettepe University , Ankara , Turkey.
authors.forename: Belma
authors.initials: B
authors.lastname: Kocer-Gumusel
authors.affiliation: a Department of Toxicology , Faculty of Pharmacy, Hacettepe University , Ankara , Turkey.
authors.forename: Pinar
authors.initials: P
authors.lastname: Erkekoglu
authors.affiliation: a Department of Toxicology , Faculty of Pharmacy, Hacettepe University , Ankara , Turkey.
authors.forename: Aydan
authors.initials: A
authors.lastname: Caglayan
authors.affiliation: a Department of Toxicology , Faculty of Pharmacy, Hacettepe University , Ankara , Turkey.
authors.forename: Filiz
authors.initials: F
authors.lastname: Hincal
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D008658:Inactivation, Metabolic; D007455:Iodine / Q000172:deficiency*; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D008297:Male; D009570:Nitriles / Q000633:toxicity*; D011722:Pyrethrins / Q000633:toxicity*; D017208:Rats, Wistar; D013963:Thyroid Hormones / Q000097:blood; D014810:Vitamin E / Q000494:pharmacology*; D015262:Xenobiotics / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D009570:Nitriles; D011722:Pyrethrins; D013963:Thyroid Hormones; D015262:Xenobiotics; D014810:Vitamin E; D007455:Iodine; C017690:fenvalerate
keywords: Cytochrome P450; Vitamin E; fenvalerate; iodine deficiency; thyroid hormones; xenobiotic-metabolizing enzymes