Lipid peroxidation in mitochondrial membranes induced by enzymatic deamination of biogenic amines

In the presence of Fe2+ and ascorbate lipid peroxidation in mitochondrial membranes is induced by incubation of membrane fragments devoid of catalase activity with amines which are the substrates of monoamine oxidases of the type B (2-phenylethylamine, benzylamine) or transformed monoamine oxidases of the type A (cadaverine). The highest stimulation of lipid peroxidation is observed in the samples containing both cadaverine and benzylamine. On the contrary, the substrate of the monoamine oxidases of the type A, serotonin, causes an antioxidative effect under these conditions. The necessary prerequisites for lipid peroxidation induction in mitochondria during their incubation with amines are i) the absence of catalase activity in the biomembranes and, ii) the presence of physiological concentrations of Fe2+. Physiological concentrations of ascorbate or pH shifts cause additional stimulation of lipid peroxidation.