Scientists discover surprising protective properties of gene linked to development of Alzheimer's disease

A new study has found a role for a genetic variant associated with Alzheimer's disease, APOE4, in protecting against glaucoma. In the work, the results of which were published in the journal Immunity, the researchers also used pharmacological treatment to successfully prevent neuronal destruction in the eyes of mice with glaucoma by affecting the APOE signaling pathway.

Specifically, the scientists demonstrated that a variant of the APOE4 gene, which increases the risk of developing Alzheimer's disease but reduces the risk of glaucoma in humans, blocks the disease cascade that leads to the destruction of retinal ganglion cells in glaucoma. In addition, they showed in selected mouse models that retinal ganglion cell death-the cause of vision loss in glaucoma-can be prevented with drugs that inhibit a molecule called galectin-3, which is regulated by the APOE gene. Taken together, these results underscore the critical role of APOE in glaucoma development and suggest that galectin-3 inhibitors may be a promising treatment for glaucoma, the authors believe.

Glaucoma is one of the leading causes of blindness, affecting approximately 80 million people worldwide. Despite the prevalence of the disease, little is known about the underlying mechanisms that lead to the loss of retinal ganglion cells, which ultimately leads to vision loss. Accordingly, there are no treatments that directly promote the survival of these cells; existing treatments, including medications, laser therapy, and surgery, focus on reducing eye pressure, the only modifiable risk factor for glaucoma. Despite these measures, however, the disease often progresses and can lead to complete blindness.