Pterygota alata (Roxb.) R. Br.: Chemical constituents, anti-hyperglycemic effect and anti-oxidative stress in alloxan-induced diabetic rats

Abstract

Twenty four compounds (4 non alkaloidal nitrogenous bases and 20 flavonoids) were isolated and identified from 70% methanol/water extract of Pterygota alata (Roxb.) R. Br. leaves and stems using chromatographic and spectroscopic techniques. The phenolics and flavonoids were qualitatively perceived through HPLC fingerprint analysis and their total contents were estimated quantitatively as 53.036 mg AE/100 g and 10.731 mg GAE/ 100 g dry weights, respectively. Potential activity of the aqueous methanol extract against alloxan inducing oxidative stress and diabetes in male rats was preliminary investigated (4 groups of 10 rats /group). Animal group receiving the extract (500 mg/kg bw i.p.) revealed a significant acute antihyperglycemic effect potentiated after 4 and 24 hrs of treatment with blood glucose levels of 202 and 160.16 mg/dl, respectively, compared to alloxan and standard Diamicron (5 mg/kg bw, p.o.) groups, as well as to a normoglycemic control group at P < 0.05. PAE significantly increased serum GSH and attenuated MDA and NO contents in rats (2.39 mmol/l, 48.16 nmol/l and 1.71 μmol/l, respectively) after 24 hrs of treatment compared to alloxan control 1.01 mmol/l, 4.69 nmol/l, 118.9 μmol/l, respectively and to normoglycemic control at P < 0.05.