Can modifying the microbiota reduce alcohol dependence?
A study in humans has shown a reduction in craving and consumption of alcohol among alcoholics following a modification of the gut microbiota via fecal transplant.
About this article
Alcoholism is a major cause of death and has serious consequences for the proper functioning of organs. Collateral damage from alcoholism includes major alterations to the intestinal microbiota, leading to a dysfunction in the dialogue between gut and brain. The intestinal microbiota is thought to play a role in behavioral disorders and addictions, and with this in mind, a team of researchers investigated whether alcohol dependence can be reduced by transferring the gut microbiota of healthy individuals to alcohol-dependent patients. To this end, twenty men aged between 60 and 70 and suffering from chronic alcoholism were divided into two groups, one of which received a fecal microbiota transplant (FMT) from a healthy donor and the other a placebo enema.
Alcohol craving and consumption reduced by FMT
Fifteen days after the FMT, the researchers observed:
– a reduction in craving for alcohol among 90% of the FMT patients, compared with 30% of the placebo patients
– a decrease in the marker molecules for alcohol consumption in the urine of the FMT patients, a sign of reduced consumption
– an improvement in the FMT patients’ cognitive performance and psychosocial wellbeing
Six months after the transplant, the FMT patients continued to report fewer serious alcohol-related problems (hospitalization, admission to emergency rooms).
Gut-brain communication involved?
The beneficial effects of FMT to treat alcohol dependence were accompanied by an increase in both microbial diversity and the abundance of short-chain fatty acids (SCFAs) in the stool and blood. High SCFA levels were associated with the presence of certain bacteria and lower addiction scores. According to the authors, the improvement in patients’ behavior in relation to alcohol may result from the increase in SCFAs following FMT, with SCFAs potentially acting as messengers that enable improved communication between gut and brain. Although preliminary, these results anticipate the introduction of therapies that alleviate alcohol addiction disorders via modulation of the microbiota.
Bajaj JS, Gavis EA, Fagan A, et al. A Randomized Clinical Trial of Fecal Microbiota Transplant for Alcohol Use Disorder. Hepatology. 2021 May;73(5):1688-1700.