Eyes may show Alzheimer's signs years before brain damage

Houston Methodist researchers report that, in a mouse model, the peripheral retina shows early changes in Muller glia and increased Aquaporin‑4 before other disease signs, suggesting the eye may reflect early Alzheimer's-related changes.

Researchers at Houston Methodist report early changes in the outer edge of the retina in a mouse model of Alzheimer's disease. The team, led by Dr. Stephen Wong, examined the peripheral retina rather than the central retina typically checked in clinical eye exams. They found alterations in retinal support cells called Muller glia and an early increase in the protein Aquaporin‑4. The study links these observations to the eye's role in clearing metabolic waste. Key findings: - The peripheral (outer) retina showed cellular and structural changes before other Alzheimer's signs in the mouse model. - Muller glia exhibited increases in size and number and showed stress-related structural changes. - Aquaporin‑4 levels rose in early stages and were associated with peripheral retinal stress. - The reported alterations are consistent with patterns seen in people diagnosed with Alzheimer's and relate to ocular glymphatic clearance. - The findings come from experiments in mice and are reported in the Journal of Alzheimer's Disease. Summary: The study indicates that peripheral retinal changes and altered markers of ocular glymphatic function appear before other disease signs in the reported mouse model. How these results translate into human screening or routine eye exams remains under study. Undetermined at this time.