Levels of Retinal Amyloid-? Correlate with Levels of Retinal IAPP and Hippocampal Amyloid-? in Neuropathologically Evaluated Individuals.

ABSTRACT: BACKGROUND:Previous studies have used immunohistology to demonstrate Alzheimer's disease (AD) characteristic accumulation of amyloid-? (A?) in the retina of AD patients, a finding indicating retina examination as a potential diagnostic tool for AD pathology. OBJECTIVE:To further explore this idea by investigating whether levels of A?42 and A?40 in retina are associated with corresponding levels in hippocampus, neuropathological assessments, apolipoprotein E (APOE) genotype, and levels of islet amyloid polypeptide (IAPP). METHODS:Levels of high molecular weight (HMW) A?42, A?40, and IAPP in ultra-centrifuged homogenates of retina and hippocampus from patients with AD, multiple sclerosis, AD with Lewy bodies, and non-demented controls were analyzed using Mesoscale Discovery electrochemiluminescence technology employing immunoassay and enzyme-linked immunosorbent assay. RESULTS:Higher levels of retinal and hippocampal A?42-HMW, A?40-HMW, and IAPP-HMW were found in individuals with high neuropathological scores of A? plaques and in individuals carrying the APOE?4 allele. The retinal levels of A?42-HMW and A?40-HMW correlated with corresponding levels in hippocampus as well as with neurofibrillary tangles (NFT) and A? scores. Retinal IAPP-HMW correlated with retinal levels of A?42-HMW and with NFT and A? scores. CONCLUSION:These results show that different isoforms of A? can be detected in the human retina and moreover support the growing number of studies indicating that AD-related pathological changes occurring in the brain could be reflected in the retina.

SUBMITTER: Schultz N 

PROVIDER: S-EPMC7081096 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature