Protective effect of thymoquinone against leiurus quinquestriatus scorpion envenomation - induced free radicals in mice

Oxidative stress has been implicated in several diseases, and extensive evidence indicates that antioxidants help to prevent organ functional damage. The present study was conducted to through light on the oxidative stress induced by Leiurus quinquestriatus [Lqq] scorpion venom and the ability of the thymoquinone [TQ], the main active constituent of the volatile oil of the black seed Nigella sativa, in ameliorating venom-induced biochemical alterations indicative of cellular injury. The present study was initiated by the determination of the LD50 of Leiurus quinquestriatus [Lqq] venom. It was found to be 34 micro g /100 g b. wt. 60 Swiss albino mice of both sexes were randomly divided into 5 groups [n = 12/group] as follows: Control group [I], Sublethal group [II] injected i.p with 25 micro g/100g.b.Wt [Lqq] venom, Lethal acute group [III] injected i.p. with 34 with micro g/100g.b.Wt of the venom, TQ pretreated sublethal group [IV] and TQ pretreated lethal acute group [V]. TQ was administrated orally by 100 micro g/kg.b.wt for one week before injection with the venom. The results showed that [Lqq] venom led to a significant increase in GSH, heart malondialdebyde [MDA] and Superoxide dismutase SOD in envenomed mice compared to the control group. On the other hand, the [Lqq] venom led to a significant decrease in glutathione peroxidase [Gpx], vitamin C and vitamin E [P value ranged between, < 0.05-0.001] in envenomed mice. The present work revealed that TQ is effective in ameliorating Leiurus quinquestriatus [Lqq] venom-evoked free radical generation and the involvement of oxidative stress in the Lqq envenomation