Oxidative metabolism of polyamines and embryonic development in Rhinella arenarum embryos exposed to azinphos methyl.

LASCANO, CECILIA; DEL BRÍO, DOLORES; FERRARI, ANA; VENTURINO, ANDRÉS

Puerto Varas

Congreso; XII PABMB Congress 2013; 2013

Polyamines (PA) are aliphatic polycations essential for the normal progression of embryonic development. We have shown that the pesticide azinphos methyl (AM) alters PA metabolism, resulting in an increase in putrescine and a decrease in spermidine and spermine. The oxidative degradation of PAs generates reactive species. Our objectives are to characterize the oxidative degradation of PAs and to determine if there is a link between this process and the alteration of embryonic development. Embryos of the toad R. arenarum were employed and the activities of diamine oxidase (DAO) and acetylpolyamine oxidase (APAO) were determined. Also, documentation of morphological alterations and a correlation analysis between enzyme activities and malformations were carried out. We observed a significant increase in DAO activity in embryos exposed to 2 mg/L AM at the end of embryonic development and a significant decrease in APAO activity at intermediate stages in embryos exposed to 0,5-, 2- and 9 mg/L AM. The number of malformed individuals increased in embryos exposed to 9 mg/L AM. However, no correlation between DAO, APAO and malformations was observed. More studies are needed to characterize the oxidative metabolism of polyamines and to determine which of the degrading enzymes, if any, contributes to the alteration of R. arenarum embryonic development.