The effect of melatonin application on lipid peroxidation during cyclophosphamide therapy in female rats

Our purpose was to investigate whether melatonin has any protective effect against lipid peroxidation induced by cyclophosphamide.

We used an animal model to study the effect of melatonin. Fifteen female Wistar rats (180-200 gram in weight) were randomly assigned to three different groups. Group 1 (n = 5) received saline injections as a control. Group 2 (n = 5) received cyclophosphamide. Group 3 (n = 5) received cyclophosphamide + melatonin. The animals were sacrificed two hours after cyclophosphamide administration and blood samples were taken and used for assaying superoxide dismutase (SOD) activity, glutathione peroxidase (GP) activity for the antioxidative enzymes, and malondialdehyde (MDA) level as an index of lipid peroxidation.

MDA levels were more increased in the second group compared with the control group (p < 0.01). In the third group, they were significantly lower than in the second group (p < 0.05). SOD and GP activities were found to be decreased significantly in the second group compared with the control group (p < 0.05 and p < 0.01, respectively). They were found to be elevated in the third group compared with the second group (p > 0.05 and p < 0.05, respectively).

The above results suggest that melatonin has a protective role in cyclophosphamide induced lipid peroxidation in rats. Besides scavenging the highly toxic free radicals, melatonin also stimulates the antioxidant enzyme activity of GP.