Methodology
Induction of diabetes in rats
Wistar rats weighing 160 ± 15 g were housed in an animal facility. The animals were acclimatized to the environment (26 ± 5°C, 55 ± 10% relative humidity, and 12 h dark/light cycle) for 1 week prior to experimental use. The rats were fed with a standard laboratory diet (Amruth feeds Pvt. Ltd, Bangalore) and water ad libitum. Ethical clearance was obtained from Institutional Animal Ethics Committee of Animal Research (IAEC approval number: UOM/IAEC/09/2012) at DOS in Zoology, University of Mysore, and experiments were carried out as per the guidelines of the committee.
The animals were divided into 4 groups and each group consisted of 5 rats:
Group 1: Control- normal untreated rats (citrate buffer injected)
Group 2: Diabetic- STZ diabetic rats
Group 3: BOvG800- STZ rats treated with BOvG (800 mg/kg body weight)
Group 4: Glibenclamide- STZ rats treated with glibenclamide (1 mg/kg body weight)
Overnight fasted animals were made diabetic by intra-peritoneal injection of freshly prepared streptozotocin in citrate buffer (0.1 M, pH 4.5) at a dose of 47 mg/kg body weight. The control rats were only injected with citrate buffer. After 96 h of induction when blood glucose was stabilized, fasting blood glucose (FBG) was determined and rats having FBG >250 mg/dl were designated as having diabetes mellitus and were used in this experiment. The experimental period lasted for 28 days and day 0 was designated as the day when rats were confirmed to be diabetic.
STZ untreated rats were left as such for the entire experimental duration. BOvG extract was dissolved in distilled water and was given orally once daily using an intra-gastric gavage for 28 days for diabetic rats. Glibenclamide (1 mg/body weight) was administered as positive control.