IN VIVO OXIDATIVE MODIFICATION OF ERYTHROCYTE MEMBRANE PROTEINS IN COPPER DEFICIENCY

Authors: SUKALSKI, KATHERINE - UNIV OF NORTH DAKOTA; LABERGE, THOMAS - UNIV OF NORTH DAKOTA; Johnson, William

Submitted to: Oxygen
Publication Type: Abstract Only
Publication Acceptance Date: 11/16/1995
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Oxidative stress has been postulated to contribute to the pathology associated with dietary copper deficiency. Activity of the important antioxidant enzyme, copper-zinc superoxide dismutase, decreases markedly in erythrocytes during copper deficiency. In vivo, erythrocytes are probably targets of oxidative damage as they are exposed to high amounts of oxygen and contain heme iron which can autoxidize, resulting in the formation of superoxide. The effect of dietary copper deficiency on indicators of oxidative stress was examined in erythrocyte membranes of rats maintained on a purified copper-deficient diet for 35 days after weaning. The cells were separated into young and old populations on a Percoll gradient prior to membrane isolation and quantification of lipid peroxides and protein carbonyls. Lipid hydroperoxides content in the membranes were very low and unaffected by copper status of the rat or age of the erythrocytes. Protein carbonyls, determined by western blot immunoassay, were detected in both the alpha and beta chains of spectrin. Alpha spectrin of erythrocyte membranes from copper-deficient rats contained higher levels of carbonyls than controls in preparations from both old and young cells.