Retinal Changes Warn of Evolution of Alzheimer’s Disease

A research team led by the Ramon Castroviejo Ophthalmology Research Institute (IIORC), the Complutense University of Madrid (UCM) and the Health Research Institute of the San Carlos Clinical Hospital (IdISSC), in collaboration with international institutions, vascular and structural changes in the retina were observed. in a mouse model of Alzheimer’s disease (AD) at the earliest stages. This discovery will open up new possibilities for early detection and monitoring of this neurodegenerative disease.

Using advanced imaging technologies such as optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA), researchers analyzed the retina of transgenic mice APPNL-F/NL-F is a model that accurately simulates part of the pathological processes of human AD. The study, published in the journal Biomolecules, covered different stages of life of mice aged 6 to 20 months and compared them with control mice of the same age.

In particular, mice revealed significant changes in the vascular structure of the retina.especially in the superficial vascular complex, as well as variations in retinal thickness: a decrease in the thickness of the inner retinal layers and an increase in the thickness of the outer layers at most points in the analysis. These structural changes precede the cognitive changes that occur in later stages of the disease.

“The APPNL-F/NL-F model is the mouse model that most closely reflects the progression of Alzheimer’s disease in humans compared to other transgenic models,” says Lidia Sanchez-Puebla, a researcher at IIORC and IdISSC.

Jose M. Ramirez, researcher in the Department of Immunology, Ophthalmology and ENT and IIORC, adds that the use of animal models “allows for disease research to be carried out in a shorter time frame because, since “Patients show signs of the disease until the first symptoms appear, which can take about 30 years.”

Early detection of AD is crucial for the management and treatment of the disease. Vascular and structural retinal changes detected by non-invasive techniques such as OCTA represent a promising tool for early diagnosis. “These findings not only facilitate the understanding of the underlying mechanisms of AD, but may also lead to the development of new early intervention strategies,” says Maria Rosa de Hoz, an IIORC researcher and co-author of the paper.

This study is the result of a collaboration between several institutions, including the Complutense University of Madrid, the Health Research Institute of the San Carlos Clinical Hospital, The National Center for Cardiovascular Research and the RIKEN Research Institute in Japan. This international collaboration network played a major role in the success of the project and highlights the importance of joining global efforts to combat neurodegenerative diseases.

“Our goal is to continue to advance these studies and explore the feasibility of implementing these imaging techniques in a clinical setting for the benefit of patients.”concludes IORC researcher Ines Lopez-Cuenca.