Synergestic effect of lycopene and Melatonin against the genesis of oxidative stress induced by cyclophosphamide in rats

Cyclophosphamide (CP) is an alkylating agent that has been considered effective for cancer treatment. Lycopene, the pigment in tomato fruits, has beneficial effect in the treatment of some diseases. The goal of this study is to evaluate the protective effect of lycopene alone or combined with melatonin (Mel) in inhibiting the oxidative stress and toxic effect of CP in rats. Five groups of rats were included in this study; Group I served as the control. Rats in groups II-V were administrated with single dose of CP (150 mg/kg B.W) interperitoneally for 3 days. On the same day of CP administration, the rats in group III were fed a diet supplemented with lycopene (50 mg/kg of diet), rats in group IV were administered with a dose of 2.5 mg Mel/kg body weight (bw) injected subcutaneously and rats in group V were supplemented with lycopene and a dose of 2.5 mg Mel/kg bw injected subcutaneously. After 15 days the blood samples were collected. Results obtained showed that CP exerted its toxic effect by increasing the free radicals and reactive oxygen species that causes lipid peroxidation and cell damage, and this in turn is detected by elevation in nitric oxide (NO) and malondialdehyde (MDA), while the activities of antioxidants enzymes including (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)) were significantly decreased as compared with the control rats. The combined treatment (Lyco + Mel) group showed potential reduction in these parameters more than those treated with lyco alone. The activities of SOD, CAT and GPx were found significantly high than lyco alone treated rats. A positive significant correlation between NO and MDA (r = .81). In conclusion, these results suggested that supplementation of diet with lycopene and Mel provided antioxidant defense with strong chemopreventive activity against Cp-induced cytotoxicity.