Apolipoprotein E ε4 is associated with neuronal loss in the substantia nigra in Alzheimer's disease

Apolipoprotein E epsilon 4 (ApoE epsilon 4) is associated with an earlier age at onset of Alzheimer's (AD) and possibly Parkinson's disease, suggesting a general role for ApoE epsilon 4 in neuronal plasticity. Among 31 prospectively assessed subjects with pathologically confirmed AD (without Lewy bodies), epsilon 4+ subjects had a longer duration of disease (by 2.8 years, p = 0.04). Only cell loss in the substantia nigra (p = 0.002) was associated with epsilon 4. Neither neurofibrillary tangles nor plaque counts were associated with epsilon 4. Cell counts of pigmented neurons in single midbrain sections in epsilon 4+ specimens were 72% of those in epsilon 4-substantia nigra (p = 0.04). These findings confirm that cell loss in the substantia nigra is associated with epsilon 4 in AD, Copyright (C) 1999 S. Karger AG,Basel.