Concomitant administration of petroleum ether extract of the stem bark of Pongamia pinnata (L.) Pierre with synthetic oral hypoglycaemic drugs in alloxan-induced diabetic mice

Aim of the studyPongamia pinnata (L.) Pierre has been used in traditional medicine for the treatment of diabetes. The aim of the study was to evaluate the effect of petroleum ether extract of the stem bark of P. pinnata (known as PPSB-PEE) by concomitantly administering with synthetic oral hypoglycaemic drugs (OHD) in diabetic mice.Materials and methodsPPSB-PEE (50 mg/kg), glyburide (10 mg/kg), pioglitazone (50 mg/kg), metformin (250 mg/kg) and repaglinide (2 mg/kg) were administered orally alone as well as concomitantly in alloxan-induced diabetic mice. After acute and chronic treatment the serum glucose level was determined. An oral glucose tolerance test (OGTT) was performed in non-diabetic as well as diabetic mice.ResultsPPSB-PEE, glyburide, pioglitazone and metformin, when administered alone and after concomitant administration, significantly (p<0.001) reduced the serum glucose level after 2, 4 and 6 h. The antihyperglycaemic effect was sustained during 21 days of administration and after a rest period of 7 days, i.e. for a total of 28 days. In an OGTT, increased glucose utilization was observed in non-diabetic as well as diabetic mice.ConclusionsIt has been concluded that the concomitant administration of PPSB-PEE with glyburide, pioglitazone or metformin, but not repaglinide, showed a synergistic antihyperglycaemic effect.