Hypoglycaemic efficacy of scoparia dulcis and costus species in albino rats

Abstract

The present study was undertaken to assess the hypoglycaemic activity of aqueous and alcoholic extract of Scoparia dulcis and Costus pictus @ 500mg/kg body weight orally in alloxan induced diabetic rats and also in combination and to compare their efficacy with a standard oral hypoglycaemic drug, glibenclamide. The experiment was conducted in seventy-two male Sprague-Dawley rats for a period of 60days, with eight animals in each group (Group I to IX). Group I served as normal control and Group II is diabetic control. Aqueous leaf extract of Scoparia dulcis and Costus pictus @ 500 mg/kg b.w orally were given to Group III and IV, respectively for 60 days. Group V and VI were given alcoholic leaf extract of Scoparia dulcis and Costus pictus @ 500 mg/kg b.w orally, respectively for 60 days. Group VII and VIII received combination of aqueous and alcoholic leaf extract of Scoparia dulcis and Costus pictus @ 500 mg/kg b.w orally, respectively for 60 days. Glibenclamide @ 0.5mg/animal/day was fed to Group IX. Body weight was recorded and RBC, WBC, total haemoglobin and glycosylated haemoglobin content were estimated on zero day, 7th, 14th, 28th, 56th, and 60th day of the experiment. Plasma glucose, plasma total lipids, plasma total cholesterol, triglycerides, plasma HDL-C, plasma total protein, plasma albumin, plasma ALT and AST were also estimated. The liver glycogen and plasma copper, iron and zinc content were estimated at the end of the experimental period. Body weight was gradually increased during the experimental period in all treated group except the diabetic control, which showed a significant (p0.001) reduction in body weight. The RBC and WBC values did not show any significant change during the entire course of the experiment and maintained a normal level. The total haemoglobin content was increased in the animals treated with combination of alcoholic leaf extract of Scoparia dulcis and Costus pictus by two months of experiment. Glycosylated haemoglobin level also significantly decreased in all the treatment groups, which is comparable to that of the animals treated with glibenclamide. The animals treated with alcoholic leaf extract of Scoparia dulcis produced a marked reduction in plasma glucose level, which was higher than the reduction produced by the animals treated with glibenclamide at the end of the experiment. The plasma total lipids and plasma total cholesterol content were markedly reduced in the animals treated with a combination of alcoholic leaf extract of Scoparia dulcis and Costus pictus, which is comparable to that produced by glibenclamide treated group. The plasma triglyceride, plasma LDL-C and VLDL-C level were markedly reduced in the animals treated with alcoholic leaf extract of Scoparia dulcis.. The HDL-C level was increased in the animals treated with combination of alcoholic leaf extract of Scoparia dulcis and Costus pictus than the animals treated with glibenclamide. The plasma total protein and albumin content was increased in the animals treated with aqueous leaf extract of Costus pictus. The globulin content and A/G ratio was increased in the animals treated with a combination of aqueous leaf extract of Scoparia dulcis and Costus pictus. The liver enzymes such as ALT and AST were reduced in the animals treated with alcoholic leaf extract of Scoparia dulcis. The liver glycogen content was increased in animals treated with alcoholic leaf extract of Costus pictus, which is comparable to that of animals treated with alcoholic leaf extract of Scoparia dulcis. The plasma copper and iron content did not show any change but the zinc content was increased in all the treated groups than the diabetic control animals.