ABSTRACT
The goal of this proposal is to investigate the role of the gut microbiota in alcohol seeking and reward-related
decision-making. Alcohol is the leading risk factor for premature death and disability for individuals between 15
and 49 years old, accounting for 3 million deaths worldwide yearly. Chronic alcohol consumption results in
escalated alcohol seeking and impaired reward-related decision-making, which are core factors in perpetuating
alcohol consumption. Mounting evidence supports a role for the gut microbiota in alcohol consumption. However,
the role of the gut microbiota in alcohol seeking and in reward-related decision-making have not been
systematically evaluated. Prebiotics, indigestible fibers that feed beneficial gut microbes, ameliorate alcohol-
induced damage to the intestinal lining, enhance cognition, and may reduce alcohol withdrawal symptoms,
suggesting that prebiotics may comprise a treatment target for the behavioral impact of alcohol. Here, we will
use operant conditioning approaches in mouse models to dissect the role of the gut microbiota in alcohol seeking
and alcohol-induced changes in reward-related decision-making. Aim 1 is to determine the role of the gut
microbiota in alcohol seeking using prebiotics to alter the microbiota (Aim 1a) and fecal microbial transplant from
prebiotic-receiving donor mice to determine a causal role for the microbiota (Aim 1b). Aim 2 is to determine the
role of the gut microbiota in alcohol-induced changes in reward-related decision-making. To test this, mice will
perform a novel, multi-stage decision-making task that we adapted directly from a human task to assess reward-
related decision-making using computational modeling. Mice will receive prebiotics (Aim 2a) or fecal transplant
from prebiotic receiving donors (Aim 2b) to determine whether prebiotics ameliorate alcohol-induced changes in
decision-making, and whether these effects are mediated by the gut microbiota. The profile of the gut microbiome
will be assessed using metagenomic sequencing and bioinformatics to determine what aspects of behavior,
intestinal permeability, and inflammation correlate with the gut microbiota. Completion of these aims will test the
feasibility of mitigating alcohol seeking and decision-making impairments by manipulating the gut microbiota
using a putative alternative treatment target and determine whether the gut microbiota play a causal role.
Dr. Thompson’s main career goal is to investigate the potential of the gut microbiota to provide alternative
treatment options for psychiatric disorders. The proposed aims will provide Dr. Thompson with crucial training,
research experience, and data that will advance this career goal. Dr. Thompson’s integrated mentorship team is
comprised of experts in addiction models, clinical and translational alcohol research, host-microbe interactions,
and computational modeling of decision-making, ensuring successful completion of the research and training
aims. Dr. Thompson will expand this mentored training through didactic and technical coursework and
professional development activities. Together, the proposed experiments and training will prepare Dr. Thompson
for an independent career investigating the role of the gut microbiota in psychiatric disorders.