Lipid peroxidation and morphological changes in mammalian cells treated with the glutathione oxidant, diamide

Chinese hamster ovary cells treated with the glutathione oxidant diamide formed large amounts of lipid peroxide. This effect was greater at 18 °C than at 0 °C and was apparently not a direct consequence of glutathione oxidation because it occurred at concentrations well above those needed to oxidize cellular glutathione. The reagent was toxic at 18 °C but not at 0 °C and caused extensive blebbing in 50% of the treated cells at this temperature. Electron microscopic examination of rabbit polymorphonuclear neutrophils disclosed that diamide caused formation of a large, organelle-free bleb and a band of fibrogranular material. It also inhibited phagocytosis of yeast particles by these cells. These effects were reversed when the cells were incubated at 37 °C in the absence of diamide. The results indicate that, although diamide is relatively specific for glutathione under some circumstances, effects observed with intact cells under most experimental conditions may reflect processes other than oxidation of endogenous glutathione.