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ADP-activated lipid peroxidation coupled to the TPNH oxidase system of microsomes

1963; Elsevier BV; Volume: 12; Issue: 5 Linguagem: Inglês

10.1016/0006-291x(63)90111-6

1090-2104

Paul Hochstein, Lars Ernster,

Free Radicals and Antioxidants

The presence of lipid peroxides, detected by the formation of malonaldehyde (MA), has been observed in tissues isolated from vitamin E-deficient animals (Zalkin and Tappel, 1960). Lipid peroxidation has also been found to occur in isolated subcellular fractions when these were incubated aerobically in the presence of hematin compounds (Tappel and Zalkin, 1960), ferrous ions (Ottolenghi, 1959; Hunter et al., 1963), and ascorbate (Ottolenghi, 1959; Thiele and Huff, 1960). In this paper, we wish to report the occurrence of a TPNH-induced peroxidation of lipids in rat-liver microsomes. The reaction requires activation by ADP or other pyrophosphates, and appears to be coupled to the TPNH oxidase system of the microsomes. The latter system was first described by Gilette et al. (1956) in connection with studies of TPNH-linked hydroxylations. Some properties of the TPNH-induced lipid peroxidation are described below and compared with those of the non-enzymically induced lipid peroxidation which occurs in the presence of ascorbate.