Microbiologists are hoping to use gut bacteria to find treatments for disorders of the brain and nervous system. Russian startup company Holobiome hopes to use the growing evidence linking gut bacteria to disorders ranging from autism to anxiety, to lead them toward advancements in treatments. (1)

Psychobiome Studies Target Many Conditions

According to Holobiome CEO, Phil Strandwitz, the team is targeting depression, insomnia, constipation, and irritable bowel syndrome (IBS) to name a few. These conditions have possible neurological and intestinal components. These microbe-based treatments, also known as “psychobiotics,” could be the answer to alleviating a long list of conditions. (1)

The Holobiome team is one of many companies interested in charging ahead to find new microbial therapies despite a lack of understanding of how psychobiotic therapies work. This could lead to issues if treatments are introduced too soon. (1)

Psychobiomes Based On Connection Between Gut And Brain

Thousands of species of microbes live in the gut. They offer the potential to create therapies that use and make nutrients and other molecules with the help of these microbes.  In fact, epidemiological researchers revealed connections between gut and brain disorders including: (1)

  • Many people with IBS suffer from depression
  • Those on the autism spectrum experience digestive problems
  • People with Parkinson’s experience constipation

As well, the Catholic University of Leuven analyzed health records of Belgians and Dutch groups studying types of gut bacteria. People in both groups with depression were missing the same two bacterial species. (1)

Psychobiome And Animal Studies

Studies on animals show gut microbes can influence the brain. While it might be hard to imagine a “fecal transplant”, when rats and mice were given fecal matter from people with Parkinson’s, schizophrenia, autism, or depression, the animals developed similar problems. However, when given fecal matter from healthy people, the symptoms in some cases were relieved. (1)

Serotonin And Tryptophan

A possible causal link is the amino acid tryptophan. This can be converted into serotonin either by the body’s own cells or microbes. Since serotonin is related to psychiatric disorders and tryptophan can also be converted into kynurenine, which can be toxic to neurons, this idea is a possibility. Depressed patients tend to convert tryptophan into kynurenine as opposed to serotonin. (1)

GABA And Psychobiomes

Meanwhile, at Holobiome, the team isolated a bacterium that requires gamma-aminobutyric acid (GABA) in order to thrive. Misregulation of GABA has been linked to mental health problems including depression. The company has now patented bacteria that helped produce GABA as a possible treatment for mental disorders. (1)

Strandwitz feels the bacteria not only boost GABA but also produce molecules that could address symptoms of depression. Despite uncertainties, as long as the bacteria is used without side effects, he hopes they can move forward with clinical trials. As the team continues to test 30 GABA producing bacteria, they believe once regulatory and ethical reviews are completed, they might very well start human trials as soon as early 2021. (1)

Holobiome’s treatment could be based on a single bacterial species, a group, or a bacteria-based compound. Strandwitz believes a wider range of species than found in typical probiotics is likely to prove more versatile. This makes it a candidate to treat multiple aspects of conditions such as depression. (1)

Sources:

https://www.sciencemag.org/news/2020/05/meet-psychobiome-gut-bacteria-may-alter-how-you-think-feel-and-act