Interaction study of aqueous extract of Pleurotus pulmonarius (Fr.) Quel-champ with acarbose in alloxan induced diabetic mice

Abstract

Mushrooms are a low calorie food with very little fat and are highly suitable for obese persons. The objective of the present investigation was to study the interaction of aqeous extract of P. pulmonarius (called PP-aqu) with acarbose on serum glucose levels, and on the oral glucose-tolerance test (OGTT) in alloxan induced diabetic mice. PP-aqu (500 mg/kg), acarbose (50 mg/kg) and their combination were administered orally in alloxan (70 mg/kg i.v.) induced diabetic mice. In the acute study, the serum glucose level was estimated at 0, 2, 4, 6 and 24 h after drug administration. The subacute study involved repeated administration of the drugs for 28 days, a serum glucose level estimation at 7, 14, 21 and 28 days and recording of the body weights of the mice. In the OGTT, D-glucose (2.5 g/kg) was administered in diabetic mice half an hour after pre-treatment with PP-aqu (500 mg/kg), acarbose (50 mg/kg) and their combination. Serum glucose levels were estimated 30 min prior to glucose administration and at 0, 30, 60 and 120 min after glucose loading. The antihyperglycaemic effects of PP-aqu and acarbose alone were similar; i.e. the onset was 2 h, the peak effect was 6 h but the effect waned at 24 h. The effect of the combination of PP-aqu with acarbose was however different, as serum glucose was lower at 24 h. In the subacute study, repeated administration (once a day for 28 days) of the acarbose, PP-aqu and combination caused a significant (P<0.001) reduction in the serum glucose level as compared to the vehicle treated group. Combination treatment prevented a decrease in the body weight of the diabetic mice. In the OGTT test, the combination of PP-aqu with acarbose increased the glucose threshold at 120 min after the administration of glucose. The combination treatment of PP-aqu with acarbose produced a more synergistic antihyperglycaemic effect than either drug alone.