Effects of oxidation on redox and cytotoxic properties of copper complex of A beta 1-16 peptide

摘要

The effect of oxidation on redox and cytotoxic properties of copper complex of amyloid beta (A beta) peptide was studied by gamma radiolysis. The oxidation of A beta 1-16 and A beta 1-16/Cu(II) complex was carried out using hydroxyl ((OH)-O-center dot) radicals produced by gamma radiolysis and the products were analyzed using mass spectrometry. The presence of Cu(II) was found to enhance the oxidation of A beta 1-16 peptide. The oxidation of residues Asp1, His6, and His13 was enhanced due to their involvement in copper binding. The oxidation of His residues of A beta 1-16 peptide, which are chiefl y responsible for copper binding, resulted in altered redox properties and subsequently in higher cytotoxicity of the A beta 1-16 peptide in SH-SY5Y cells.