Antidiabetic effect of Eclipta alba associated with the inhibition of alpha-glucosidase and aldose reductase

The antidiabetic effect of the ethanolic extract of Eclipta alba (EEA) on hyperglycaemia and diabetic nephropathy was investigated in streptozotocin-induced diabetic rats. Single-dose treatment of EEA to streptozotocin-induced diabetic rats lowered the blood glucose level by 17.6% (p < 0.05) at 250 mg kg(-1) dose after 5 h post oral administration. Treatment of animals after 10 weeks of STZ-treatment with EEA (250 mg kg(-1)) for 21 days significantly reduced the elevated levels of blood glucose, % HbA1C, urea, uric acid and creatinine, and significantly increased the depressed serum insulin level. The extract exerted a significant inhibitory effect on alpha-glucosidase in a noncompetitive manner with an IC50 value of around 54 mu g mL(-1) and was found inhibitory to eye lens aldose reductase with an IC50 value of around 4.5 mu g mL(-1). The results suggest that EEA possesses antidiabetic effect associated with alpha-glucosidase and aldose reductase inhibition.