Abstract
Hog kidney diamine oxidase (DAO) interacted with 1,3-diaminopropane, putrescine and cadaverine to arrest proliferation of cultured mammalian cells. The byproducts of DAO-substrate interaction, H2O2 and NH are themselves cytotoxic but were apparently not responsible for any significant antiproliferative effect in the experimental system. DAO is known to react with putrescine to generate labile 4-aminobutyraldehyde. This primary product was compatible with a compound (radio-labelled) separated from DAO-putrescine reactive mixtures by ion-exchange chromatography. Its rate of generation, level attained and lability (half-life, 2 hr) in culture simulated conditions were measured. Circumstantial evidence suggested that the amine aldehyde products of diamine oxidation had a potent antiproliferative effect on cells.