The effects of genistein supplementation on fructose induced insulin resistance, oxidative stress and inflammation

AimsThis experimental study was designed to investigate the effects of 10 weeks genistein administration on oxidative stress and inflammation in serum and liver of rats fed with fructose.Main methods6–8 weeks old, 40 male Sprague-Dawley rats were included. Group 1 (control) was fed with standard chow food and 100 μl/kg/day/rat dimethyl sulfoxide (DMSO) administered subcutaneously; group 2 (genistein) with standard chow food and 0.25 mg/kg/day/rat genistein; group 3 (fructose) with standard chow food and drinking water 20% fructose, group 4 (fructose + genistein) with standard chow food, drinking water with 20% fructose and 0.25 mg/kg/day/rat genistein. TNF-α, IL-6, visfatin as inflammatory markers and 8-isoprostane as a oxidative stress marker were measured by ELISA, glucose, triglyceride, total cholesterol, LDL-cholesterol and HDL-cholesterol by enzymatic colorimetric method, AST and ALT by kinetic UV method.Key findingsSignificantly high 8-isoprostane levels in serum (p < 0.001) and liver (p < 0.05) in group 3 compared to control group indicate that presence of oxidative stress. Significantly high TNF-α and IL-6 levels in serum (p < 0.05) and liver (p < 0.01) and visfatin levels in serum (p < 0.001) of group 3 indicate inflammation accompanying insulin resistance and oxidative stress. Genistein administration to fructose group causes a significant decrease in HOMA-IR (p < 0.001) and LDLC (p < 0.05) level. Significantly lower serum 8-isoprostane (p < 0.01) level indicates the antioxidant effect of genistein and significantly lower liver TNF-α (p < 0.01), serum, liver IL-6(p < 0.01) and serum visfatin (p < 0.01) levels reflect the antiinflammatory effects of genistein.SignificanceGenistein administration to rats fed with fructose causes an ameliorating effect on HOMA-IR values and lipid status markers in addition to its antioxidant and antiinflammatory effects.