According to new research from Weill Cornell Medicine, certain types of bacteria normally found in our gastrointestinal tract could influence the immune system during a stroke, thus reducing the severity. As stroke is the second leading cause of death throughout the world, this finding is very welcome and promising news.
The study, which was published in a recent edition of Nature Medicine, involved administering a combination of antibiotics to mice. After two weeks, the research team induced an ischemic stroke, the most common type where an obstruction in the blood vessel stops the blood from reaching the brain. They found that the mice who had received the antibiotics experienced a much less severe stroke than those mice who hadn’t been given any medication. In some cases the stroke was up to 60% smaller. The researchers believed that this reduction in severity was due to the microbial environment in the GI tract directing the gut’s immune cells to protect the brain and shield it from the full force of the stroke.
Research shows a new relationship between the brain and the gut
The researchers conclude that their studies have shown a new relationship between the brain and the gut, and that microbiota in the intestine have a significant influence on the outcome of a stroke. Furthermore, they have suggested that it will be possible to modify the microbiota in the gut to develop innovative ways to prevent a stroke occurring. This could prove extremely helpful for people at a high risk of stroke, including those who are about to undergo cardiac surgery.
While further research is necessary to gain a greater understanding of the precise bacterial components, the team did conclude that the beneficial effect was not as a result of the bacteria interacting with the brain chemically, but rather that they had influenced the survival rate of the neurons through modification of the immune cells’ behaviour. The immune cells move from the gut to the outer covering of the brain, where they collect to respond to the stroke.
This new finding has positive implications for future stroke prevention, particularly as this might be achieved by getting those people at risk of stroke to change their dietary habits, rather than treating them with drugs. However, further research is now needed to identify the beneficial bacteria.