Anti-hyperglycemic activity of heliotropium strigosum (Boraginaecae) whole plant extract in alloxan-induced diabetic mice

Purpose: To investigate Heliotropium strigosum whole plant extract for its potential to reduce the blood glucose level of alloxan-induced diabetic mice. Methods: Preliminary phytochemical analysis was carried out using standard procedures. Diabetes was induced in Balb/c mice by injecting alloxan (200 mg/kg i.p.). The crude methanol extract of Heliotropium strigosum (Hs.Cr, 30, 100 and 300 mg/kg doses) was administered daily to alloxan-induced diabetic mice for 15 days and its effect on fasting blood glucose levels, body weight and oral glucose tolerance was evaluated. Two control groups (non-diabetic control and diabetic control) received normal saline (0.2 ml). Metformin (500 mg/kg) was used as reference standard. Results: Heliotropium strigosum showed positive for the presence of alkaloids, tannins and flavonoids. The extract (30, 100 and 300 mg/kg) caused significant reduction in the fasting blood glucose level of alloxan-induced diabetic mice on days 5, 10 and 15 compared to diabetic control (p < 0.001). In this regard, the anti-hyperglycemic effect compared to the reference (metformin). The extract also time-dependently decreased the body weight of the treated animals as well as improved tolerance of the oral glucose overload. Conclusion: These results indicate that Heliotropium strigosum possesses anti-hyperglycemic effect, reduces body weight and enhances the tolerance of glucose overload in mice. Further studies are therefore required to determine its feasiilty as an alternate herbal medicine in the management of diabetes in humans.