Evidence of oxidative damage in Alzheimer's disease brain: central role for amyloid beta-peptide

Amyloid β-peptide (Aβ) is heavily deposited in the brains of Alzheimer's disease (AD) patients. Free-radical oxidative stress, particularly of neuronal lipids, proteins and DNA, is extensive in those AD brain areas in which Aβ is abundant. Recent research suggests that these observations might be linked, and it is postulated that Aβ-induced oxidative stress leads to neurodegeneration in AD brain. Consonant with this postulate, Aβ leads to neuronal lipid peroxidation, protein oxidation and DNA oxidation by means that are inhibited by free-radical antioxidants. Here, we summarize current research on phospholipid peroxidation, as well as protein and DNA oxidation, in AD brain, and discuss the potential role of Aβ in this oxidative stress.