Exploring Microbial Signatures in Individuals with Prolactin-Secreting Pituitary Adenoma: Unraveling Microbiome Variations and Underlying Markers

Abstract

Background Alterations in the intestinal flora composition can influence host inflammation, metabolism, and immune response. While extensive research has explored gut dysbiosis in various pituitary adenomas (PA), the changes in gut microbiota composition and their correlations with clinical parameters 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 16S rRNA gene amplicon sequencing, we examined the gut microbiota community in the PPA group and investigated its associations with clinical characteristics. 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: 0.959). 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. Our comprehensive 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.