Young Gut Bacteria Make Old Mouse Brains Act Young

Scientists study gut bacteria in mice. They write about this in June 2026. Gut bacteria are very small. They live inside the stomach. Some bacteria help the brain.

Young mice have young brains. Their brains can change easily. We call this brain plasticity. But old brains do not change easily.

In Italy, researchers do an experiment. They use very young mice. The young mice are twenty-one days old. The researchers give them antibiotics. The antibiotics are in their water. The mice drink this water for ten days.

Antibiotics kill many gut bacteria. They kill families like Lachnospiraceae. This bacterium is good for the brain. The chemicals protect the nerve cells.

The scientists close one eye of the mice. They close it for three days. They check the eyes and brains. Only the control mice show changes. The other mice have damaged brains.

Next, scientists do another experiment. They use old adult mice. These mice are four months old. They receive bacteria from young mice. These young mice are thirty days old.

Another group receives old bacteria. This is the control group. The scientists close one eye of these mice. They look at their brains.

Control mice brains do not change. But the other old mice are different. Their brains receive young bacteria. Their brains change in the test. The brains act like young brains. They have good brain plasticity.

Scientists in Norway and Ireland talk about this. The gut bacteria are very important. They help the brain grow. They can change the brain.

But humans are not mice. Human brains are very complex. Diet and lifestyle change human bacteria. People need many more studies. The new tests can help us.