Antiglycation and hypolipidemic effects of polyphenols from Zingiber officinale roscoe (Zingiberaceae) in streptozotocin-induced diabetic rats

Abstract

Purpose: To evaluate the antiglycation and hypolipidemic potential of polyphenols from Zingiber officinale in streptozotocin-induced diabetic rats. Methods: Diabetes was induced in male Wistar rats by single intraperitoneal injection of 50 mg/kg body weight (bw) of streptozotocin. This was followed by oral administration of 500 mg/kg each of free and bound polyphenol extracts of Z. officinale to the rats daily for 42 days. Distilled water and glibenclamide (5 mg/kg) were used as normal and positive controls, respectively. Results: Significant increases (p < 0.05) in blood glucose level (369.26 mg/dL), serum advanced glycation end-products (AGEs) (6.80 μg/mL), lipid profile and atherogenic indices, with decrease in high density lipoprotein cholesterol (HDL-C) (15.55 mg/dL) were observed in diabetic rats compared to control. Free polyphenol extracts of Z. officinale significantly reduced (p < 0.05) blood glucose (147.96 mg/dL), serum AGEs (1.98 μg/mL), lipid profile and atherogenic indices while it significantly increased HDL-C (23.28 mg/dL). However, bound polyphenol extract did not cause any significant change in the lipid profile of the diabetic rats except for LDL-C. Conclusion: This study indicates that free and bound polyphenols from Z. officinale can ameliorate diabetes as well as its complications, and its effect is comparable to that of the standard drug, glibenclamide.