Gut microbiota composition and functionality are associated with prolactin-secreting pituitary adenoma and serum lipid levels.

BACKGROUND: The changes in gut microbiota composition and their correlations with serum lipid levels in prolactin-secreting pituitary adenoma (PPA) patients remain unknown. This study investigates these alterations and associations and explores microbial markers for PPA diagnosis. METHODS: A total of 101 participants were enrolled, comprising 72 PA patients (31 with prolactin-secreting adenomas and 41 with non-functioning adenomas, i.e., PPA and NFPA groups) and 29 age and sex-matched healthy controls (HC). Utilizing 16 S rRNA gene amplicon sequencing, we examined the gut microbiota community in the PPA group and investigated its associations with serum lipid levels. RESULTS: Our results revealed significantly reduced microbial ecosystem richness and evenness in PPA patients compared to healthy controls. The PA group, especially PPA, exhibited substantial alterations in gut microbiota structure, including increased abundance of gram-negative pathogenic bacteria such as Desulfovibrio and Enterobacter, and decreased levels of probiotic bacteria like Bifidobacterium. We also identified significant positive correlations between PPA-enriched bacteria and serum lipid levels. A biomarker panel (including Bifidobacterium, Dorea, Blautia, Morganella, Desulfovibrio, and Enterobacter) demonstrated good performance in differentiating between PA patients and healthy controls (AUC: 0.843). Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis unveiled dysregulations in fundamental physiological pathways, particularly lipid metabolism, within the PPA group. CONCLUSIONS: Our findings suggest that PA patients, particularly those with PPA, exhibit distinct host-microbe interactions compared to healthy controls. Notably, the intestinal flora, particularly in the PPA microenvironment, may play a role in contributing to tumor development by impacting fundamental metabolism, especially lipid metabolism. IMPORTANCE: Our study revealed that the gut microbiome is tightly linked to PPA, and the disturbed microbiome may regulate the risk of PPA in lipid metabolism. These findings, including the development of a biomarker panel, suggest the potential of intestinal flora as a diagnostic and predictive tool, emphasizing its significance as a preventive target for PPA.