Activation of Rat Erythrocyte Superoxide Dismutase by Copper
Red blood cell superoxide dismutase (SOD) activity levels have been used to assess human copper status1,2. Initially, there was concern that these values may not accurately reflect the progress of copper repletion of people previously in poor copper status. This concern arose because red cell proteins do not undergo the usual turnover and synthesis processes3. A preexisting copper-free SOD apoprotein will not necessarily bind copper newly introduced into the body. Such is the case for rat serum ceruloplasmin which will only incorporate copper before secretion by the liver4. For these reasons, administration of copper to people in poor copper status might not be expected to quickly raise erythrocyte Cu-Zn SOD activity contents to copper adequate values. Possibly, a new red cell population would have to be generated. However, in practice, copper repletion restores human red cell SOD activities faster than could be accounted by normal production of new red cells with normal SOD activities1,2. The present study used rats to elucidate the mechanisms by which copper repletion increases erythrocyte SOD activities.
KeywordsPyrogallol Autoxidation Erythrocyte Superoxide DISMUTASE Human Copper Adequate Copper Typical American Diet
- 3.E. Beutler, “Red Cell Metabolism, a Manual of Biochemical Methods,” 2nd Ed., Cruse and Stratton, New York (1979).Google Scholar
- 5.J. Prohaska, Changes in tissue growth, concentrations of copper, iron, cytochrome oxidase, and superoxide dismutase subsequent to dietary or genetic copper deficiency in mice. J. Nutr. 113: 2148 (1983).Google Scholar