Forming New Neurons With Help From Gut Microbes

According to scientists, gut microbes that metabolize tryptophan release molecules that stimulate the production of new neurons in the adult brain.

AsianScientist (Jul. 20, 2021) – Here’s some food for thought: teeny microbes in our guts may support the formation of new nerve cells in adult brains. In fact, gut microbes may even prevent memory loss in old age, as well as help repair nerve cells after injury. These findings were published in the Proceedings of the National Academy of Sciences of the United States of America.

If you’ve ever felt butterflies in your stomach or gone with your gut, then you’ve unknowingly felt the influence of your so-called ‘second brain’—otherwise known as our gut. After all, hidden within the twists and turns of our intestines are billions of microorganisms that not only help metabolize food, but also play roles in protecting the body against harmful pathogens.

Now, an international team of scientists spanning Singapore to Sweden have discovered a new function for the teeming masses of microbes in our guts: helping form new nerve cells in adult brains.

Led by Professor Sven Pettersson from the National Neuroscience Institute of Singapore, the team found that gut microbes that metabolize the essential amino acid tryptophan secrete small molecules called indoles, that in turn, spur the development of new brain cells in adults.

The team also demonstrated that the indole-mediated signals stimulate key factors know to be important in forming new adult neurons in the hippocampus—an area of the brain associated with memory and learning.

“This finding is exciting because it provides a mechanistic explanation of how gut-brain communication is translated into brain cell renewal, through gut microbe-produced molecules stimulating the formation of new nerve cells in the adult brain,” explained Pettersson.

According to the authors, their findings bring us a step closer to new treatment options to slow down memory loss associated with ageing and neurodegenerative diseases like Alzheimer’s.

For instance, researchers could design drugs could mimic the action of indoles to stimulate the production of new neurons in the hippocampus or even develop diets with indole-enriched food products that could slow down ageing.

“We are currently assessing whether indoles can also stimulate early formation of neurons during brain development. Another area of potential intervention interest is in situations of stroke or spinal injury where there is an urgent need to generate new neurons. It is an interesting and exciting time ahead of us,” concluded Pettersson.

The article can be found at: Wei et al. (2021) Tryptophan-metabolizing Gut Microbes Regulate Adult Neurogenesis via the Aryl Hydrocarbon Receptor.


Source: National Neuroscience Institute; Photo: Shutterstock.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Asian Scientist Magazine is an award-winning science and technology magazine that highlights R&D news stories from Asia to a global audience. The magazine is published by Singapore-headquartered Wildtype Media Group.

Related Stories from Asian Scientist