Inhibition of glycation reaction in tissue protein incubations by water soluble rutin derivative.

In the Maillard reaction, nonenzymatic glycation reaction reversibly produces Amadori rearrangement products which subsequently lead to the formation of irreversible advanced glycation end-product (AGE). These reactions are important in the pathogenesis of complications associated with diabetes. This study examined the antioxidant activity of rutin and related efficacy to inhibit glycation in three distinct tissue protein sources. Rutin and the rutin analogue exhibited significant antioxidant activity in a liposomal model reaction similar to quercetin. Incubation of rat muscle and kidney proteins with 50 mM glucose for 5 days resulted in the generation of N(epsilon)-fructoselysine (FL), a biomarker for initial stage glycation. The addition of G-rutin, a water soluble glucose derivative of rutin, to the incubation medium (0.1 mM) reduced (p < 0.05) FL production. AGE content in both muscle and kidney proteins was also increased (p < 0.05) with the addition of glucose in the incubation mixture, but completely suppressed by the presence of G-rutin. On the contrary, inhibition of FL and AGE formation by G-rutin was found to be comparatively less effective in bovine serum albumin than both muscle and kidney proteins. These results demonstrate that the antioxidant activity of G-rutin corresponds to a strong affinity to suppress the formation of both initial and advanced stages of Maillard reaction in tissue protein sources.