ASSOCIATION BETWEEN GUT MICROBIOME AND DRINKING TYPES OF ALCOHOL USE DISORDER

Abstract Background Alcohol use disorder (AUD) presents as a diverse condition, with clinical characteristics linked to treatment effectiveness varying among individuals. For example, distinct patterns of drinking exhibit distinct reactions to Naltrexone therapy. Individuals classified as reward drinkers tend to display a higher likelihood of positive response to Naltrexone treatment. Utilizing the gut-brain axis mechanism as a foundation, we explore disparities in gut microbiome profiles across various drinking patterns. Methods So far, a total of 36 patients diagnosed with AUD were included in the study, and their drinking patterns were evaluated following the guideline. DNA was extracted from the patients' stool samples, and high-throughput sequencing was employed for 16S rRNA data analysis, which was subsequently analyzed through bioinformatics methods. The AUD patients were categorized into four groups based on their reward and relief levels: low reward/low relief (4 subjects), high reward/low relief (2 subjects), low reward/high relief (9 subjects), and high reward/high relief (21 subjects). Results Analysis of alpha diversity in the stool samples from these groups revealed no significant differences in the microbial community richness. However, beta diversity analysis using NMDS, PCA, and PCoA indicated statistically significant distinctions in the stool microbiome patterns among the four groups. Additionally, we conducted pairwise comparisons between low and high reward as well as relief groups using LDA. The analysis revealed a higher frequency of Bacillales and a decreased occurrence of Bacteroides species, including uniformis and fragilis, in the high relief group. Studies have linked Bacteroides uniformis and Bacteroides fragilis to depression in both human and mouse models. Moreover, Parabacteroides distasonis was more prevalent in low reward subjects compared to the high reward group and has been associated with inducing depression-like behavior in mouse models. Conclusion Various patterns in the gut microbiome are expected among different types of alcohol use disorder (AUD). Certain bacteria linked to specific drinking patterns have been associated with depression. Subsequent research should explore the clinical aspects related to these drinking patterns, considering the alterations in gut bacterial composition in individuals with AUD.