EFFECT OF DIETARY CARNOSINE ON PLASMA AND TISSUE ANTIOXIDANT CONCENTRATIONS AND ON LIPID OXIDATION IN RAT SKELETAL-MUSCLE

The effect of dietary carnosine supplementation on plasma and tissue carnosine and alpha-tocopherol concentrations and on the formation of thiobarbituric acid reactive substances (TBARS) in rat skeletal muscle homo-genates was evaluated. Plasma, heart, liver and hind leg muscle was obtained from rats fed basal semipurified diets or basal diets containing carnosine (0.0875%), alpha-tocopheryl acetate (50 ppm), or carnosine (0.0875%) plus alpha-tocopheryl acetate (50 ppm). Dietary carnosine supplementation did not increase carnosine concentrations in heart, Liver and skeletal muscle. Dietary supplementation with both carnosine and alpha-tocopherol increased carnosine concentrations in liver 1.56-, 1.51- and 1.51-fold as compared with diets lacking carnosine, alpha-tocopherol or both carnosine and alpha-tocopherol, respectively. Dietary supplementation with both carnosine and alpha-tocopherol also increased a-tocopherol concentrations in heart and liver 1.38-fold and 1.68-fold, respectively, as compared to supplementation with alpha-tocopherol alone. Dietary supplementation with carnosine, alpha-tocopherol or both car-nosine and alpha-tocopherol was effective in decreasing the formation of TBARS in rat skeletal muscle homogenate, with dietary alpha-tocopherol and alpha-tocopherol plus carnosine being more effective than dietary carnosine alone. The data suggest that dietary supplementation with carnosine and alpha-tocopherol modulates some tissue carnosine and alpha-tocopherol concentrations and the formation of TBARS in rat skeletal muscle homogenates.