Liposome-encapsulated glycyrrhizin alleviates hyperglycemia and glycation-induced iron-catalyzed oxidative reactions in streptozotocin-induced diabetic rats

Glycyrrhizin, a bioactive constituent of Glycyrrhiza glabra has been reported to ameliorate diabetes. Here, the effects of liposome-encapsulated glycyrrhizin on STZ-induced diabetes and associated oxidative stress were investigated. Wistar rats were grouped as control (NC, received placebo), diabetic (DC, STZ-induced), diabetic treated with free glycyrrhizin (DTG, 3 i.v. doses, 1.6 mg/0.5 ml), empty liposomes (DTl, 3 i.v. doses), and liposome-encapsulated glycyrrhizin (DTbd, 3 i.v. doses, 1.6 mg/0.5 ml). Serum glucose, insulin, intraperitoneal glucose tolerance test and glycohemoglobin were estimated. Free iron and iron-mediated oxidative stress were examined. Histological examinations of the kidney and liver were performed. Liposomal-glycyrrhizin treatment caused significant improvement of hyperglycemia (DC vs. DTbd p p p p p p p p p 2O2 vs. DTbd + H2O2 p 2O2 vs. DTbd + H2O2, p