Effect of synergic dietary calcium enrichment and induced ferropenic anemia on antioxidant enzymes activity in rats.

OBJECTIVE: The aim of this study was to examine the synergism of dietary calcium enrichment (added to goat's or cow's milk) and induced nutritional ferropenic anemia on oxidative status.

METHODS: Control rats and rats with induced nutritional ferropenic anemia were fed for 14 d with diets containing normal (5000 mg/kg) or double (10 000 mg/kg) the recommended calcium content. Thiobarbituric acid-reactive substances in plasma were measured, as were the activities of the antioxidant enzyme catalase, copper/zinc superoxide dismutase, and glutathione peroxidase in erythrocyte cytosol.

RESULTS: Dietary calcium enrichment did not affect oxidative stress as assessed by thiobarbituric acid-reactive substances; however, it significantly upregulated the activities of some antioxidant enzymes examined in the erythrocyte cytosol. In particular, adding calcium to standard or milk-based diets significantly increased glutathione peroxidase activity in control and anemic rats and copper/zinc superoxide dismutase activity in control rats.

CONCLUSION: The increased activities of glutathione peroxidase and copper/zinc superoxide dismutase induced by dietary calcium enrichment suggest that calcium supplementation may protect against oxidative stress even in nutritionally induced ferropenic anemia.