Free Radical Scavenging Activity of Calotropis gigantea on Streptozotocin-Induced Diabetic Rats

Swarnabhasma, an Ayurvedic preparation containing Calotropis gigantea R. Br. (Asclepiadaceae) is extensively used by Ayurvedic physicians for treatment of diabetes mellitus, bronchial asthma, rheumatoid arthritis and nervous disorders. In the present study, we report the effect of chloroform extracts of Calotropis gigantea leaf and flower on free radical scavenging activity, and lipid profile in streptozotozin-induced diabetic rats. The lipid peroxidation, superoxide dismutase, and catalase were measured in liver homogenate and serum glutamic pyruvic transaminase, serum glutamic oxaloacetic transaminase, alkaline phosphatase, lipid profile were measured in blood serum. Administration of single dose of streptozotozin (55 mg/kg, i.p.) caused significant increases in lipid peroxidation, serum glutamic pyruvic transaminase, serum glutamic oxaloacetic transaminase, alkaline phosphatase, cholesterol and triglyceride levels, while superoxide dismutase and catalase levels were significantly decreased. Further, administration of chloroform extracts of Calotropis gigantea leaf and flower to streptozotocin-induced diabetes rats at a dose of 10, 20 and 50 mg/kg orally for 27 d lead to a significant decrease in lipid peroxidation, serum glutamic pyruvic transaminase, serum glutamic oxaloacetic transaminase, alkaline phosphatase, cholesterol and triglyceride levels. Consequently, superoxide dismutase and catalase levels were significantly increased. Glibenclamide was used as a positive control (10 mg/kg). It was observed that the effect of chloroform extracts of Calotropis gigantea on alkaline phosphatase, cholesterol, superoxide dismutase, serum glutamic pyruvic transaminase, serum glutamic oxaloacetic transaminase, levels are comparable to that of those produced by the positive control.