Selenium modulates peroxidation in the absence of glutathione peroxidase in Musca domestica.

Adult houseflies fed a low-selenium diet showed a 73% decrease in total Se compared to those given 1.0 ppm Se in their drinking water. This decrease was associated with a 84.4% increase in thiobarbituric acid reactants and a 16.3% increase in conjugated dienes. These increases were unrelated to activities of glutathione S-transferases, superoxide dismutases and catalase and to levels of reduced and oxidized glutathione, all of which were unaltered by Se deficiency. Since houseflies lack glutathione peroxidase, Se apparently modulates peroxidation in these animals independent of the antioxidant enzymes and glutathione.