Lipid peroxidation of human erythrocyte ghosts induced by organic hydroperoxides

Isolated human erythrocyte ghosts perform lipid peroxidation, measured as malondialdehyde, induced by cumene hydroperoxide and t-butyl hydroperoxide but not by H2O2. In contrast to Ames et al. (Ames, B.N., Cathcart, R., Schwiers, E. and Hochstein, P. (1981) Proc. Natl. Acad. Sci. 78, 6858-6862), no inhibition is found by uric acid, only an increase in lag-time of the malondialdehyde production. In parallel with the malondialdehyde production, fluorescent chromolipids are also formed. Both processes are blocked by the addition of desferal, a potent iron chelator. The malondialdehyde production is also inhibited by the OH radical scavenger, thiourea, and by the anti-oxidant, butylated hydroxytoluene. Treatment of erythrocyte ghosts with cumene hydroperoxide or t-butyl hydroperoxide leads to the genesis of high-molecular-weight protein, but not with H2O2. The appearance of high-molecular-weight proteins is accompanied by disappearance of protein bands, e.g., the alpha- and beta-spectrin band, the anion-exchanger and some other smaller bands. Furthermore, a protein band is formed in the lower-molecular-weight region. 4. The addition of desferal does not reveal any blockade of the high-molecular-weight protein genesis. In contrast, a marked diminution of high-molecular-weight proteins is observed by the addition of thiourea, accompanied by a protection of the protein bands which would otherwise disappear. Similar results are obtained with butylated hydroxytoluene. 5. It is concluded that under oxidative stress the process of high-molecular-weight protein genesis can occur independently of the lipid peroxidation process, measured as the revealing of malondialdehyde.