Why this is important:
- Gut microbiome disruption and poor neural synapse pruning have been linked to a range of neuropsychiatric conditions like autism spectrum disorder.
- New research in zebrafish by University of Oregon neuroscientists shows that gut microbes encourage specialized cells to prune back extra connections in brain circuits that control social behavior.
- The UO team also identified two defining features of that set of social neurons that may be shared by mice and zebrafish.
- The findings could lead to new treatments for a range of neurodevelopmental conditions.
How it works:
- Pruning is a normal part of healthy brain development. Extra neural connections can get in the way of the ones that really matter, resulting in muddled messages.
- In this research, gut microbes in healthy zebrafish spurred cells called microglia to prune back extra links between neurons. In fish without those gut microbes, the pruning didn’t happen, and the fish showed social deficits.
- The team also identified two defining features of that set of social neurons that may be shared by mice and zebrafish. One is that those cells could be identified by having similar genes turned on, a clue that they might serve similar roles in the brains of both species. That finding strengthens the researchers’ belief that their work in zebrafish could translate to mice or humans.
- “This is a big step forward,” said UO neuroscientist Judith Eisen, who co-led the work with neuroscientist Philip Washbourne. “It also sheds light on things that are going on in larger, furrier animals.”
- Washbourne’s lab previously identified a set of neurons in the zebrafish brain that are required for one particular kind of social interaction.
- “We’ve known for a while that the microbiome influences a lot of things during development,” Washbourne said. “But there hasn’t been a lot of concrete data about how the microbiome is influencing the brain. We’ve done quite a bit to push the boundary there.”
- News release on study: https://around.uoregon.edu/content/new-five-year-grant-funds-study-bacteria-brain-development
- Judith Eisen bio: https://ion.uoregon.edu/research/faculty-page/92
- Philip Washbourne bio: https://ion.uoregon.edu/research/faculty-page/268
- Washbourne Lab: https://blogs.uoregon.edu/washbournelab/