Submitted to: Recommended Dietary Allowances Workshop
Publication Type: Abstract Only
Publication Acceptance Date: 9/10/1997
Publication Date: N/A
Technical Abstract: Cytochrome c oxidase (CCO) activity in rat platelets declined with dietary Cu content when diets contained 3 ug Cu or less per gram of diet. The decline in platelet CCO activity also corresponded closely to reductions in liver Cu, plasma Cu, plasma ceruloplasmin oxidase activity, and erythrocyte superoxide dismutase (SOD) activity. Furthermore, platelet CCO activity was better than either erythrocyte SOD or ceruloplasmin activities for predicting liver Cu concentrations. Platelet CCO activity may also be a sensitive indicator of Cu status in humans. Eight of ten postmenopausal women consuming a diet that provided 0.6 mg of Cu per day for 105 days experienced 17% to 54% decreases in platelet CCO activity. Although erythrocyte SOD activity also was decreased during Cu deprivation, neither plasma Cu nor ceruloplasmin was significantly affected in the women. These findings indicate that platelet CCO activity has sufficient sensitivity to be regarded as an index of Cu status. However, it remains to be determined if decreased platelet CCO activity during Cu deprivation is a prognosticator of any pathology associated with Cu deficiency.