Thymoquinone treatment against acetaminophen-induced hepatotoxicity in rats

Aim: In this study, we aimed to examine the efficacy of thymoquinone (TQ) treatment in acetaminophen-induced liver toxicity in rats. Methods: Forty Wistar Albino rats were used for the study (four groups, with 10 rats for each group). Animals in the control group were not given any medication. In the thymoquinone (TQ) group, animals were given three times 5 mg/kg oral thymoquinone for every six hours, which equals to a total dose of 15 mg/kg. In the acetaminophen (APAP) group, animals were given APAP at a single dose of 500 mg/kg orally. In the APAP + TQ group, animals were given 500 mg/kg APAP orally followed by three doses of TQ at a 15 mg/kg total dose in an 18-h time interval. All animals were sacrificed at the 24th hour. Alanine amino transferase (ALT), aspartat amino transferase (AST), superoxide dismutase (SOD), oxidized glutathione (GSSG), glutathione peroxides (GSH-Px), and malondialdehyde (MDA) activities were measured in rat blood. Histopathological examination was also performed. Results: Serum ALT, AST levels, GSSG, and SOD activity as well as the serum and tissue MDA levels were found to be higher in the APAP group than in the control group (p <= 0.001). Likewise, serum GSH-Px activity was found to be lower in the APAP group (p <= 0.001). In contrast, in the APAP + TQ group, serum ALT, AST levels, GSSG, SOD activity and the serum and tissue MDA levels were found to be lower compared to that of the APAP group. This difference was statistically significant (p <= 0.001). In the APAP + TQ group, the GSH-Px activity was found to be significantly higher compared to the APAP group (p < 0.05). In contrast to this finding, the GSH-Px activity in the APAP + TQ group was found to be lower than that of the control group (p <= 0.001). Histopathological analysis revealed significant liver necrosis and toxicity with a high dose of APAP where TQ treatment was related with significantly lower liver injury scores. Conclusion: TQ treatment may have an important therapeuthic effect via the upregulation of antioxidant systems in the APAP-induced liver hepatotoxicity in rats. (C) 2013 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.