Potent Protective Effect Of α -Tocopherol And Fish Oil On In Vivo Paraquat Induced Oxidative Damage In Rats

Abstract

The potential protective role of α-tocopherol and fish oil against oxidative damage induced by paraquat were investigated. Forty male albino rats with average body weight of 100-120 gm were housed in 8 groups of 5 rats each. The first group served as control and injected with saline, group 2 was injected with a single dose of paraquat (10 mg/kg, intraperittoneally) for 24 h prior to decapitation (P), group 3 was administered orally with vitamin E (100 mg/kg) five times a week (E), group 4 was administered orally with fish oil (20 mg/kg) five times a week (FO); group 5 received FO+E, groups 6, 7 and 8 were administrated with P+E, P+FO and P+E+FO respectively. The content of microsomal proteins, drug metabolizing enzymes and thiobarbituric acid reactive substances (TBARS) were determined in liver microsome after treatment. Vitamin E together with fish oil significantly decreased the content of cytochrome b5 (p<0.01), cytochrome P-450 (p<0.001), glutathione-S-transeferase (p<0.001) and cytochrome C-reductase (p<0.001) when given before paraquat injection. Meanwhile, this combination of vitamin E and fish oil significantly (p<0.05) increased amidopyrine N-demethylase. On the other hand vitamin E and fish oil alleviated the paraquat induced increase in TBARS.
In conclusion, oral administration of vitamin E and fish oil are effective in reducing the activity of selected drug metabolizing enzymes and are also effective in reducing lipid peroxidation process caused by paraquat. So, these combinations provide a potent protection against paraquat-induced oxidative toxicity in rats\' liver.


Keywords: Fish oil; Vitamin E; Paraquat; Microsomal Enzymes; GST; TBARS.

Egyptian Journal of Biochemistry and Molecular Biology Vol. 26 (2) 2008: pp. 1-12