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

Amyloid beta -peptide (A beta) 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 A beta is abundant. Recent research suggests that these observations might be linked, and it is postulated that A beta -induced oxidative stress leads to neurodegeneration in AD brain. Consonant with this postulate, A beta 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 A beta in this oxidative stress.