Antidiabetic and Antioxidant Effects of the Polyherbal Drug Glucoblock and Glibenclamide in Type 2 Diabetic Rats

The increased prevalence of diabetes, and the huge disease burden on patients has led to an increase in the use of complementary and alternative medicine in diabetes treatment and management.

Aim: This study evaluates the antidiabetic and antioxidant effects of the polyherbal capsule glucoblock and glibenclamide in type 2 diabetic rats.

Methodology: A total of 35 male Wistar albino rats weighing between 120-220 g were used for this study. The rats were placed on high fat diet, and diabetes induced by a single intraperitoneal injection of freshly prepared streptozotocin (STZ) (45 mg/kg body Wt). Fasting plasma glucose (FPG) was determined using the glucose oxidase method. Fasting plasma insulin (FPI), total oxidant status (TOS), total antioxidant status (TAS) and superoxide dismutase (SOD) levels were quantitatively determined by a rat-specific sandwich-enzyme linked immunosorbent assay (ELISA) method. Insulin resistance (IR) was determined using the homeostatic model assessment of insulin resistance (HOMA-IR) method. Oxidative stress index (OSI) was determined by the ratio of TOS to TAS. Phytochemical analysis was also done on the herbal capsule.

Results: Mean FPG levels were significantly lower (p˂0.05) in all groups, compared to the diabetic control. Mean FPG level was significantly higher (p˂0.05) in the combination group, but showed no significant difference (p>0.05) in the glibenclamide group, and glucoblock group, compared to the negative control. HOMA-IR was significantly higher (p<0.05) in the diabetic control compared to the negative control and treatment groups. The combination group had significantly higher (p˂0.05) HOMA-IR values, whereas the individual treatment groups showed no significant difference (p>0.05) when compared to the negative control. TOS was significantly higher (p<0.05) in the diabetic control compared to the negative control and treatment groups. The treatment groups showed no significant difference (p>0.05) in TOS, compared to the negative control. There was significantly lower (p˂0.05) TAS levels in the diabetic and treatment groups, compared to the negative control. OSI values were significantly lower (p˂0.05) in all groups when compared to the diabetic control. Also, OSI values were significantly higher (p˂0.05) in the treatment groups compared to the negative control. SOD was significantly lower (p<0.05) in the diabetic control compared to the negative control and treatment groups. The treatment groups showed no significant difference (p>0.05) in SOD levels, compared to the negative control.

Conclusion: Increase in total oxidant status and oxidative stress depleted antioxidant parameters. The polyherbal capsule glucoblock was effective when used alone and produced equipotent effect to the treatment with glibenclamide. However, the combination treatment did not fare better. Antioxidant therapy should be used together with antidiabetics in the management of diabetes, and care should be taken in the use herb-drug combinations.