Mechanism of the cytotoxic effect of l-amino acid oxidase isolated from Bothrops alternatus snake venom

BaltLAAO-I, an L-amino acid oxidase isolated from Bothrops alternatus, is a glycoprotein enzyme with a pI⿿5.3, 15% sugar and a related molecular mass of 66,000 Da in its monomeric form, and 123,000 Da in its dimeric form. The objective of this study is to describe the cytotoxicity activity induced by BaltLAAO-I isolated from Bothrops alternatus venom and its possible mechanism of action on tumor cells. Our results clearly depict that BaltLAAO-I has a strong selective cytotoxic activity on tumor cell lines (JURKAT, SK-BR-3 and B16F10). On the other hand, the results show low cytotoxicity on human peripheral blood mononuclear cells. Furthermore, our findings demonstrate that BaltLAAO-I induces the apoptosis of tumor cell lines through a cytotoxic activity exerted by a generation of reactive oxygen intermediates. All in all, the data indicate that LAAOs exert a selective cytotoxic role on tumor cells, demonstrating a great potential for future use in clinical therapy.