Antioxidant Properties of Thymol and Butylated Hydroxytoluene in Carbon Tetrachloride – Induced Mice Liver Injury

Abstract

Thymol and Butylated hydroxytoluene (BHT) were tested for their ability to inhibit carbon tetrachloride (CCl4)-induced lipid peroxidation in mice liver. To achieve this purpose, four groups of mice were tested, GP I: Animals served as normal control, GP II: Animals injected i.p. with a single dose of CCl4 (0.5 ml/kg B.W), GP III and IV: Animals pretreated by oral administration of thymol or BHT for 6 days, then injected with a single dose of CCl4. After the experimental period, blood was collected, sera separated for ALT assay. The antioxidant activities of the enzymes; superoxide dismutase (SOD), glutathione peroxidase (GS-PX) together with malondialdhyde level were assayed in liver tissues. Results obtained showed that, the antioxidant enzyme activities were significantly decreased while the level of Malondialdhyde (MDA), the indicator of lipid peroxidation, and the activity of alanine aminotransferase (a liver function test) were significantly increased following i.p injection with single sub-lethal hepatotoxic dose of CCl4 as compared to control. Pretreatment of CCl4-intoxicated mice with thymol or BHT for 6 days showed a significant increase in the activities of antioxidant enzymes with simultaneous significant decrease in the level of MDA and ALT as compared to CCI4-treated rats. BHT was a little more potent than thymol in its action. Histopathological examination revealed a necrotic lesion in liver of mice injected with CCl4. Pretreatment with thymol or BHT ameliorates the deleterious effect of CCl4. This is confirmed by the normal appearance of liver tissue. It was speculated that thymol and BHT exert their effects by decreasing lipid peroxidation and enhancing the activities of antioxidant enzymes. For this reason, thymol could be used as hepatoprotective agent with free medication side effects.