Antidiabetic and antidyslipidemic activities of aqueous leaf extract of Dioscoreophyllum cumminsii (Stapf) Diels in alloxan-induced diabetic rats

Abstract

Ethnopharmacological relevance: Dioscoreophyllum cumminsii (Stapf) Diels leaves are used in the management of diabetics in Nigeria. Thus, the antidiabetic activity of aqueous D. cumminsii leaf extract and its capability to halt oxidative stress and dyslipidemia in alloxan-induced diabetic rats was investigated.

Methodology: Antidiabetic was evaluated in alloxan-induced diabetes rats. Diabetic rats were treated with 50, 100 and 200mg/kg body weight of the extract.

Result: The aqueous extract of D. cumminsii leaves significantly reduced blood glucose level in a dose dependent manner with highest dose producing 72% reduction after 21 days administration, which was compared significantly (P<0.05) with the control group and glibenclamide treated groups. Similarly, aqueous extract of D. cumminsii significantly reversed reduction in insulin in alloxan-induced diabetic rats. Alloxan-induced diabetic mediated alterations in liver and serum cholesterol, triacylglycerides, high-density lipoprotein cholesterol (HDLc), low density lipoprotein cholesterol (LDLc) and very low-density lipoprotein cholesterol (VLDLc) were significantly (P<0.05) restored by the extract. Aqueous extract of D. cumminsii leaves significantly attenuated the decrease in the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose 6-phosphate dehydrogenase in the liver and pancreas of alloxan-induced diabetic rats. Elevation in the concentration of malondialdehyde was significantly (P<0.05) lowered by D. cumminsii leaves extract. The diabetic-mediated alteration in the architecture of liver was alleviated by the extract.

Conclusion: Overall, aqueous extract of D. cumminsii leaves at all doses investigated reduced blood glucose level and prevented oxidative stress and dyslipidemia in alloxan-induced diabetic rats.

Keywords: Diabetes; Dioscoreophyllum cumminsii; Dyslipidemia; Insulin; Lipid peroxidation; Oxidative stress.