Purpose: To investigate the effect of total hydroalcohol root extract of
Plumeria alba
(Apocynaceae)
and its active fraction on diabetes in rats.
Methods: The effect of total hydroalcohol extract at 250 mg/kg and different fractions was evaluated on
oral glucose tolerance test (OGTT) in mice. The effect of the active fractions on OGTT was measured
on a model of diabetic rats (fructose-enriched fat diet and streptozotocin-induced).
Results: The results show that the total extract (250 mg/kg), ethyl acetate fraction and supernatant
fraction (obtained after centrifugation of total extract) at a dose of 100 mg/kg significantly (p < 0.01)
reduced hyperglycemia induced by glucose overload in mice. Fructose-enriched fat diet increased blood
cholesterol, triglycerides and high density lipoprotein (HDL) levels in hyperlipidemic untreated rats
compared to normal control rats. Administration of total extract (250 mg/kg/day) and supernatant
fraction of
P. alba (100 mg/kg/day) during 14 days significantly reduced lipid parameters (total
cholesterol, p < 0.001; triglycerides, p < 0.01; HDL, p < 0.05). Analysis of oxidative stress markers
shows that the supernatant fraction and total extract significantly increased serum glutathione level (p
< 0.01) but significantly lowered malondialdehyde (MDA) concentration in liver (p < 0.05).
Conclusion: These results suggest that the total extract and fractions of
P. alba exhibit significant
antidiabetic and hypolipidemic properties in streptozotocin-induced diabetic animals. The supernatant
fraction (which is free of organic solvent) was the most biologically active
