Abstract
Rutin and hesperidin, which are known as vitamin P, have antioxidant activities, and are expected to exhibit preventive or therapeutic effects on many diseases. However, in spite of their useful effects, their use has been limited because of their low water solubility. Glucosylated vitamin P (GVP) shows improved solubility; it dissolves in water to a 10, 000-fold greater extent than conventional vitamin P. In this study, we evaluated the antioxidant property of GVP, and investigated whether GVP is effective against oxidative stress mediated by free radicals in hyperlipidemia. GVP was found to exhibit the same antioxidant efficacy as vitamin P in vitro. The plasma of rats after oral administration of GVP showed a decrease of lipid peroxides induced by copper sulfate. Furthermore, GVP significantly reduced the serum total cholesterol (Chol) and HDL-Chol levels in mice with hyperlipidemia induced by a high-fat diet. The lipid peroxide level in serum and eyeballs increased in the mice, suggesting an increase of oxidative stress. GVP significantly decrease the level of lipid oxidation. In addition, GVP also suppressed the overproduction of interleukin (IL)-1β, interferon (IFN)-γ and IL-4 in the mice, but not to a significant extent. These results indicate that GVP exhibits antioxidant activity in vivo and that this effect is probably associated with the suppression of lipid hydroperoxide and the inflammatory response, which are elevated in hyperlipidemia.
