Evaluation of the Effects of Water Melon Seed Oil (Citrullus lanatus) on Cadmium Induced Cerebral Toxicity in Male Wistar Rats

Cadmium is a toxic heavy metal that accumulates predominantly in soft tissues and as such is currently one of the most important occupational and environmental pollutants. The study evaluated the potential protective effects of watermelon seed oil on cadmium-induced toxicity in the cerebrum of male Wistar rats. Group 1 recieved 2 ml/kg of distilled water. Group 2 received 5 mg /kg bwt of cadmium chloride only. Group 3 received 5 mg /kg bwt of cadmium chloride + 500 mg / kg btw of CLSO as high dose. Group 4 received 5 mg /kg bwt of cadmium chloride + 250 mg / kg btw of CLSO as low dose. Group 5 received 5 mg /kg bwt of cadmium chloride + 10 mg / kg bwt of succimer. The administration was done through oral intubation and lasted 28 days. The experimental animals were observed daily and weighed weekly for physical changes. Neuro- behavioral study on anxiety related behaviors was accessed weekly using elevated plus maze test. On the 29 th day of the experiment, the final body weights were taken and euthanized using 75 mg /kg ketamine IP. The brain tissues were homogenized using 5 times (w/v) homogenizing buffer (pH 7.4). The homogenate was centrifuged at 4000 rpm to get the supernatant for biochemical analysis. While organ/ body weight revealed no significant changes, behavioral study show that Citrulus lanatus seed oil significantly (p<0.05) increased rearing frequency, grooming frequency and the number of entry into the open arm of the elevated plus maze relative to control. The biochemical assay showed statistically increased mean MDA across the groups when compared with the control (p <0.001). Although, there were statistical decrease SOD and GSH of the treated groups (p <0.001) when compared with the control, the mean CAT showed no significant difference across the groups in relation to the control. The histology showed that Co-treatment with CLSO prevented the neuronal degenerations of the cerebral cortex when compared with the control. CLSO ameliorated the effects of CdCl2–induced degeneration of cerebral cortex neurons, thus demonstrating its potential to protect cerebral cortex neurons from cadmium toxicity.

Key Words: Cadmium chloride. Oxidative stress, Toxicity Citrulus lanatus, Histology