Identification of pongamol and karanjin as lead compounds with antihyperglycemic activity from Pongamia pinnata fruits

Aim of the studyTo identify pongamol and karanjin as lead compounds with antihyperglycemic activity from Pongamia pinnata fruits.Material and methodsStreptozotocin-induced diabetic rats and hyperglycemic, hyperlipidemic and hyperinsulinemic db/db mice were used to investigate the antihyperglycemic activity of pongamol and karangin isolated from the fruits of Pongamia pinnata.ResultsIn streptozotocin-induced diabetic rats, single dose treatment of pongamol and karanjin lowered the blood glucose level by 12.8% (p < 0.05) and 11.7% (p < 0.05) at 50 mg /kg dose and 22.0% (p < 0.01) and 20.7% (p < 0.01) at 100 mg/kg dose, respectively after 6 h post-oral administration. The compounds also significantly lowered blood glucose level in db/db mice with percent activity of 35.7 (p < 0.01) and 30.6 (p < 0.01), respectively at 100 mg/kg dose after consecutive treatment for 10 days. The compounds were observed to exert a significant inhibitory effect on enzyme protein tyrosine phosphatase-1B (EC 3.1.3.48).ConclusionThe results showed that pongamol and karangin isolated from the fruits of Pongamia pinnata possesses significant antihyperglycemic activity in Streptozotocin-induced diabetic rats and type 2 diabetic db/db mice and protein tyrosine phosphatase-1B may be the possible target for their activity.