Astrocyte Protein RTP801 Implicated in Cognitive Decline in Alzheimer's Disease

Researchers at the University of Barcelona's Institute of Neurosciences have uncovered new molecular insights into the progression of Alzheimer's disease, a leading cause of dementia. Their study highlights the critical role of the RTP801 protein within astrocytes—key support cells in the brain—that contributes to cognitive decline characteristic of the disease. Conducted on animal models, the research demonstrates that silencing RTP801 expression in astrocytes of the hippocampus can reduce abnormal brain connectivity and neuroinflammation, offering potential new avenues for therapy.

Alzheimer's disease involves the accumulation of beta-amyloid plaques outside neurons and hyperphosphorylated tau proteins inside neurons, leading to progressive neurodegeneration. The RTP801 protein, encoded by the DDIT4 gene, has been previously linked to neuroinflammation and neurotoxicity, but its role specifically within astrocytes was not well understood. This study, published in "Alzheimer's & Dementia," for the first time shows that RTP801 in astrocytes influences neuroinflammatory responses, synaptic regulation, and brain network activity.

Using gene therapy techniques, the team silenced RTP801 in dorsal hippocampal astrocytes in animal models of Alzheimer’s. They observed a decrease in hyperconnectivity of brain networks, suggesting that modulating RTP801 levels could restore healthier brain function. Additionally, the reduction of RTP801 helped improve the levels of GABA, an inhibitory neurotransmitter crucial for proper neural function, by protecting GABA-producing parvalbumin-positive interneurons. These findings suggest that RTP801 toxicity may impair inhibitory circuits in the hippocampus, leading to disrupted brain activity.

The study also explored the relationship between RTP801 and neuroinflammation markers, such as astrogliosis and microgliosis, indicating that reducing RTP801 expression can diminish neuroinflammatory responses. Overall, these discoveries point to RTP801 as a promising target for therapies aimed at slowing or reversing cognitive decline associated with Alzheimer's. The researchers plan to further investigate these mechanisms and develop strategies to translate these findings into clinical applications.

This work, led by researcher Almudena Chicote-González and colleagues, provides new insights into how astrocytes contribute actively to neurodegeneration, emphasizing that targeting astrocytic functions could be pivotal in future treatments for Alzheimer's disease.

Source: https://medicalxpress.com/news/2025-05-astrocyte-protein-rtp801-contribute-cognitive.html