Protein-based biomarker in eye fluid can single out Alzheimer’s disease

“One of the biggest priorities in Alzheimer’s disease research is to develop ways to diagnose the disease before the onset of symptoms, so as to allow for early treatment,” said Manju Subramanian from the Department of Ophthalmology at Boston Medical Center (BMC), US. Subramanian is one of a few scientists who have recently discovered a promising Alzheimer’s biomarker in ocular fluid samples, which would allow for more specific diagnostic eye tests for the neurodegenerative disease.

The BMC scientists collected eye fluid samples during routine eye surgery from 77 subjects and upon analysis detected levels of a protein called neurofilament light chain (Nfl), released as a result of brain cell damage. Nfl is said to be directly related to Alzheimer’s disease; it can be detected in blood and cerebrospinal fluid many years, or even decades, before clinical symptoms appear.

In the 77 subjects, increased levels of eye-related Nfl were associated with higher levels of other biomarkers of Alzheimer’s such as amyloid and tau proteins. At the same time, the Nfl levels were not associated with any clinical eye diseases, or general systemic diseases, including diabetes.

“We hope that these results will add another way to use information about what’s happening in different parts of the body to detect the presence of disease before neurodegeneration takes hold, causing irreversible damage,” said Subramanian. “The earlier we can diagnose and treat these diseases, the better off our patients will be.”

The scientists are working on detecting Nfl levels in more accessible ocular fluids, such as tear secretions. If a less invasive way of procuring ocular fluid is found then broad eye testing could be deployed as an early diagnostic for many other neurodegenerative diseases as well.

Category: Uncategorized