Silencing neurons changes support and immune cells in mice
Experiments in adult and middle-aged mice found region-specific changes in brain support and immune cells after researchers blocked communication from selected nerve cells.
Limit: Nerve-cell projections also degenerated, complicating attribution of glial changes to silencing alone
Edited by Boris Djordjevic · AgingResearch.News
In an animal experiment, researchers blocked chemical communication from selected nerve cells in mice aged 12–16 weeks and eight months. They deleted Snap25, a gene needed for nerve cells to release chemical signals, and compared these mice with controls. Brain support- and immune-cell measurements used five to six mice per genetic group at the younger ages and four to five at eight months.
Astrocytes, cells that support neurons, reacted strongly in silenced regions of the cortex, the brain’s outer layer. These regions also had a higher density of microglia, the brain’s immune cells. Connected regions showed changes in microglial shape and organization and in connections between neurons. Age amplified differences among astrocytes and microglial responses. The authors suggested that the arrangement of brain circuits shapes these region-specific responses.
Why it matters
The work addresses how aging alters the response of brain support and immune cells to prolonged disruption of nerve-cell communication.
Caveats
The genetic mouse model also showed progressive degeneration of nerve-cell projections, complicating interpretation of responses to silencing alone. The cell markers did not capture the full range of astrocyte responses or define a specific microglial activation state.
The paper
Deletion of Snap25 disrupts glial remodeling in aging mouse brain
University of Oxford
iScience, Jun 23, 2026, Open access
