Evaluation of the Cardioprotective Effect of Citrullus lanatus (Watermelon) Seeds in Streptozotocin Induced Diabetic Albino Rats

The study examined the cardioprotective potential of the ethanolic extract of Citrullus lanatus in streptozotocin induced diabetic albino rats. A total of sixty albino rats weighing approximately ± 200 g were used. The induction of diabetes in the rats was done using 50 mg/kg body weight of streptozotocin and confirmed by checking glucose levels using a glucometer. Albino rats with glucose levels greater than ≥ 250 mg/dl were considered diabetic. The rats were divided into 5 groups of 12 animals each and allowed access to food and water ad libitum. The animals had a 12 hour overnight fast after which diabetes was induced by injecting them intraperitoneally with streptozotocin (50 mg/kg). The control (group A) was not induced while diabetic control was induced. Induced diabetic rats in groups C, D and E were later treated with C. lantus at a dose of 100 mg/kg, 400 mg/kg, 800 mg/kg body weight respectively for 14 and 28 days respectively. After 14 days, 6 rats in each of the groups were sacrificed while the remaining 6 were sacrificed after 28 days. Blood samples were collected into lithium heparin bottles and used for the assay of cardiac enzymes (creatine kinase and lactate dehydrogenase) using standard procedures. The data obtained were compared using one-way analysis of variance (ANOVA) and the difference between means was obtained using Tukey's multiple tests of comparison. Analyses showed that the levels of creatine kinase (CK-MB) and lactate dehydrogenase(LDH) in the albino rats treated with C. lanatus were significantly (p<0.05) reduced when compared with the diabetic-induced group without treatment and the decrease was dose-dependent. A significant decrease (p<0.05) in the levels of the enzymes was also observed based on the duration of treatment with the extract. Since the enzymes are markers of cardiac injury, the decrease in their activity following treatment with C. lanatus shows that the extract possesses the significant cardioprotective potential of ameliorating structural integrity of the cardiac muscle in diabetic condition.