Peroxide-like oxidant response in lungs of newborn guinea pigs following the parenteral infusion of a multivitamin preparation

The multivitamin solution is a major component responsible for the photo-in duced generation of peroxides in parenteral nutrition. The lung is a target of oxidant injury; however, the specific role of infused peroxides is unkn own. The aim of this study was to determine if parenteral multivitamins ind uce in the lung an oxidant challenge similar to that of peroxides. Newborn guinea pigs were infused with dextrose plus relevant concentrations of H2O2 (0, 250, 500 mu M) or multivitamins (0, 1%) as well as parenteral nutritio n supplemented with multivitamins (0, 1%). After 4 days, total glutathione, glutathione-related enzymes, and oxidant-sensitive eicosanoids were measur ed in the lungs. Peroxides as well as multivitamins led to a significant de crease in glutathione and the activity of glutathione synthase, indicating that infused peroxides were not entirely transformed into free radicals, wh ich would have stimulated glutathione synthesis. The multivitamin solution induced a response in oxidant-sensitive eicosanoids similar to the response to peroxides, suggesting an oxidant stress that was not alleviated by the antiradical properties of its components. The effects on prostaglandins occ urred independently from the stimulation in glutathione levels induced by p arenteral nutrition. The multivitamin solution carries an oxidant load and causes effects similar to those of peroxides in the lungs of newborn guinea pigs. (C) 2000 Elsevier Science Inc.