Genetic mutations in the ε4 allele of apolipoprotein E (APOE) have been associated clinically with increased dementia risk and pathologically with increased Aβ plaque load. A new study, led by researchers from the University of Kentucky, detected the ApoE protein in dementia brains from participants with and without the APOE ε4 risk allele. Findings were published in the American Journal of Pathology. Researchers analysed several proteins from the amygdalae of 40 participants from the University of Kentucky Alzheimer’s Disease Center autopsy cohort.
The amygdala is a brain region vulnerable to mis-aggregated proteins associated with dementia. Participants ranged from cognitively normal to severe dementia. As expected, people with dementia had significantly higher Tau and Aβ protein levels than the normal and mild cognitive impairment group. The data also revealed a close correlation between dementia diagnosis and the detection of ApoE peptides in the brain, including from people lacking the APOE ε4 risk allele. Overall, the correlation for ApoE peptides with dementia was even stronger than that seen for Tau or Aβ. In the present study, researchers suggested a link between the non-mutated Apolipoprotein E and dementia in the aging brain.