By Olivia Trani
 
Researchers from Virginia Commonwealth University’s School of Medicine are conducting a clinical trial to better understand how transplantation of beneficial microscopic organisms in the gut, called gut microbes, could help people overcome their addiction to alcohol.
 
The study, called Intestinal Microbiota Transplant in Alcohol-Associated Liver Disease (IMPACT), is the latest work led by Jasmohan Bajaj, M.D., a professor in the Department of Internal Medicine’s Division of Gastroenterology, Hepatology and Nutrition in the VCU School of Medicine and a physician at the Richmond Veterans Affairs Medical Center. He has been investigating the relationship between microbiomes, liver health and addiction-related diseases for the past several years.

Jasmohan Bajaj, M.D., has been investigating the relationship between microbiomes, liver health and addiction-related diseases for the past several years. (contributed photo)

“Excessive alcohol use has been a growing issue in the United States in recent decades, which only became worse as a result of COVID-19. We have young people in their twenties and thirties with end-stage liver disease who basically found themselves adrift during the pandemic,” Bajaj said. “Intestinal microbe transplantation could potentially be an additional tool to help patients overcome addiction.”

We spoke with Bajaj to learn more about the relationship between the gut and our health. 

How do the microbes in our gut impact our health and behaviors?

Our digestive system is home to a diverse ecosystem of bacteria and other microorganisms. Many of these microbes play key roles in maintaining our health and helping our bodies function, like digesting nutrients and warding off infection. Some research has shown that the microbes in our gut may also play a part regulating our brain and behavior. More than 100 million nerve cells line our gastrointestinal tract, allowing our gut and brain to communicate with each other through chemical signals.

There is an intense neuronal connection between the brain and the gut. If you change the gut environment significantly enough, you have the potential to not only impact the brain, but also in some ways our behavior.

How are gut microbes and alcohol use connected?

When the microbial communities residing in our bodies are thrown out of balance, such as from excessive drinking or other unhealthy habits, it can lead to various health problems. This, in turn can affect our brain and the liver. Through this research, we are looking to better understand how the opposite can be true as well. If we restore balance in our microbiota, we want to know if this has a positive effect on our health, especially on the gut and the brain.

In an earlier, small-scale clinical trial, we extracted beneficial bacteria from a healthy person’s stool and transplanted them into patients with severe alcohol use disorder and advanced liver disease. The patients that received the microbial transplant experienced a reduction in alcohol craving and consumption, as well as improved brain function and quality of life, after 15 days. The microbial transplant also translated into fewer hospitalizations from alcohol-related complications compared to the placebo group.

What treatments currently exist for managing alcohol addiction?

Several treatment options have shown to help people with alcohol use disorder. This includes behavioral treatments, which aim to help manage drinking behavior through goal-setting, coping strategies, and other forms of counseling. Mutual-support groups like Alcoholics Anonymous (AA) can also be an approach for helping people with alcohol addiction. In addition, the U.S. Food and Drug Administration has approved a number of medications that physicians can prescribe to help reduce the urge to drink. However, these are not often used or tolerated in patients with liver disease due to alcohol and some of these may not be well tolerated over a long period.

Ultimately, not every single patient with alcohol use disorder will have the same response to a therapy or medication, which is why it’s important to have a variety of options available to meet an individual's specific needs. We are hoping to see if microbial transplantation could potentially be another option in our toolbox for helping people overcome alcohol addiction.  

What will happen during your new clinical trial and what are your goals for it?

The goal of our first clinical trial was to assess the safety of microbiota transplantation for patients. This new study will allow us to follow participants with a more detailed alcohol behavioral focus to see whether this method has a prolonged positive impact in a larger group. This is being done in collaboration with Alexander Khoruts, M.D., a professor from the University of Minnesota Medical School.  
 
Roughly 40 participants will be randomly assigned to receive capsules containing freeze-dried gut microbiota from healthy human donors twice during the study. A similar number of participants will receive placebo pills. Through surveys and regular clinical check-ups, the researchers will assess how each participant’s alcohol use and cravings, health outcomes, and gut microbiome change in the seven months following treatment.