Comparison of the Effects of Cyclodextrin-Naringin Inclusion Complex with Naringin on Lipid Metabolism in Mice Fed a High-Fat Diet

Naringin has antioxidant and antihyperlipidemic properties, however, phenolic compounds including naringin are unstable in the presence of light, heat and oxygen. Beta-cyclodextrin (β-CD) is a cyclic heptamer composed of seven glucose units that enhances the stability and solubility of molecules through the formation of inclusion complexes. This study was conducted out to compare the effects of CD-naringin (CD-N) inclusion complexes with naringin on lipid metabolism in high fat-fed animals. Male C57BL/6 mice were fed either CD-N (0.048%, w/w) or naringin (N, 0.02%, w/w) in a 20% high-fat (HFC, 15% lard, 5% corn oil, w/w) diet for 10 weeks. Orlistat (Xenical, 0.01%, w/w) was used as a positive control (PC). There were no differences in body weight, food intake, liver and heart weights, plasma triglyceride(TG), leptin, adiponectin, resistin, IL-1β and IL-6 concentrations, and hepatic β-oxidation, carnitine palmitoyl transferase(CPT), glucose-6-phosphate dehydrogenase (G6PD) and malic enzyme activities between the HFC and CD-N groups or between the HFC and N groups. However, both CD-naringin and naringin supplementation les to a significant reduction in the epididymal and perirenal white adipose tissue weights, plasma free fatty acid, insulin and blood glucose concentrations, hepatic cholesterol and TG contents and hepatic fatty acid synthase (FAS), phosphatidate phosphohydrolase (PAP) and HMG-CoA reductase activities compared to the HFC group. The plasma HDL-cholesterol concentration was significantly higher in CD-N and N groups than in HF and PC groups. These results indicate that both CD-naringin and naringin supplementation effectively improved plasma and hepatic lipid metabolism without differences between CD-N and naringin groups.