Alzheimer's disease (AD) is a neurodegenerative disease that is characterized by a decline in memory and cognition due to the formation of beta-amyloid plaques and tau proteins in the brain tissue.
Similar beta-amyloid peptide changes were noted in the retina, decades earlier than the actual appearance of cognitive decline, by Maya Koronyo-Hamaoui, Ph.D., associate professor of Neurosurgery and Biomedical Sciences and co-corresponding author of the study.
The idea was expanded by the research team at Cedars-Sinai Department of Neurosurgery, published in the journal Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring. Retina is a thin layer located at the back of the eyes and is responsible for our vision. It is the direct outgrowth of the central nervous system (brain).
The researchers utilized a non-invasive technique sectoral retinal amyloid imaging to record retinal images in participants, older than 40 years of age with cognitive decline. Peripheral regions of the retina correlate better to the brain damages associated with cognition. Hence the analysis of the retinal images was done using a new process detecting these peripheral regions.
Earlier researches done by Koronyo-Hamaoui had highlighted the role of the retina in predicting the hallmarks signs of AD.
"We found that increased levels of retinal amyloid-beta peptides correlated with levels found in brain tissues, even in the latest stages of Alzheimer's disease. We also suggested a particular type of immune-modulation therapy that may combat the disease by reducing toxic proteins and harmful inflammation in the brain and, in return, enhancing a protective type of immune response that preserved the connections between neurons, which are tightly connected to cognition", said Koronyo-Hamaoui.
This study might contribute to a precise and early diagnosis of Alzheimer's disease, that affects nearly 5.5 million people in the U.S., thereby formulating a novel treatment for the patients.