Effect of Opuntia ficus - indica L. Fruit on Blood Glucose Level in Streptozocin Induced Diabetic Rats

Background: Diabetes mellitus is a prevalent metabolic disorder. Insulin and oral hypoglycemic drugs are the basis of diabetes therapy. Nevertheless they have important side effects and are not always satisfactory in maintaining euglycemia and avoiding late stage diabetic complications. With a disturbing rise in the prevalence of diabetes and associated healthcare costs, interest in anti-diabetic plants has grown. Objective: The effects of the Opuntia ficus-indica L. fruit on the fasting blood glucose levels and body weights of the non-diabetic and streptozocin induced diabetic rats were studied. Methods: Wistar male adult rats, seven in each group, were used. To make each rat diabetic, streptozocin at the dose of 50 mg/kg was injected intraperitoneally. Fasting blood glucose level (after fasting for 12 hours) of each rat was measured by using a glucometer through taking a blood drop following cutting the tip of the tail, before streptozocin injection and after 1, 3, and 5 weeks of streptozocin injection and at the same time the animals were weighed. The blood glucose levels and weights of non-diabetic rats were measured in the same way as diabetic rats. The criterion for being diabetic was fasting blood glucose level above 200 mg/dl one week after streptozocin injection. The seeds and pulp of the fruit of Opuntia ficus-indica L. each at the doses of 6 and 12 g/kg daily as a mixture with regular rat food in the form of pellets were administered to diabetic rats 1 week after streptozocin injection for 4 weeks. Further, glibenclamide at the daily dose of 5 mg/kg mixed with regular food as pellets was administered to a separate group of diabetic rats for 4 weeks. The seeds and pulp of the fruit each at the daily doses of 12 g/kg mixed with regular rat food as pellets were also administered to non-diabetic rats for 4 weeks. Results: One way analysis of variance demonstrated that seeds and pulp of the fruit did not have any significant effects on blood glucose levels and weights of diabetic as well as non-diabetic rats in comparison with control groups after 4 weeks of drug use (p>0.05). Glibenclamide after 2 weeks of administration significantly lowered blood glucose level of diabetic rats (p<0.01) but increased their weight as compared with control diabetic rats (p<0.01).While after 3 and 5 weeks of streptozocin injection, the weights of the control diabetic group decreased as compared to the control non-diabetic group (p