CHARACTERISTICS OF THE TAXONOMIC STRUCTURE OF THE MICROBIOTA OF TESTICLES AND URETHRA IN MEN WITH NON-OBSTRUCTIVE AZOOSPERMIA WITH DIFFERENT OUTCOMES IN ART PROTOCOLS

Aim. To carry out a comparative analysis of the taxonomic structure of the testicular and urethral microbiota of patients with non-obstructive azoospermia (NOA) in ART protocols with positive (live birth) and negative outcomes. Materials and methods. The samples of testicular tissue and urethra of infertile patients with NOA (n=62) were evaluated. To realize the reproductive potential, all patients underwent micro-TESE in the ART protocol. All patients were retrospectively divided into two groups. In group 1, there were patients with NOA and a positive ART result (n=16), while in group 2 patients had NOA and a negative ART result (n=46). To study the bacterial diversity of testicular tissue, an analysis of amplicons of the bacterial 16S rRNA gene was performed using high-throughput NGS. Results. A comparative analysis of the relative representation of bacterial taxa in the testicular tissue of patients with NOA with positive and negative ART outcomes revealed a number of significant differences. For example, significant differences (p<0.05) were found in the relative representation of the phylum Fusobacteriota, the Pasteurellaceae, Dialisteraceae, Porphyromonadaceae, Alcanivoracaceae, Neisseriaceae_563222, Ruminococcaceae, Acutalibacteraceae, Peptostreptococcaceae_256921, Marinilabiliaceae, Exiguobacteraceae, Coprobacillaceae, Bacillaceae_H_289398, Burkholderiaceae_A_595427 in patients of group 1. Significant differences (p<0.05) were also found in the frequency of occurrence of the phylum Fusobacteriota, the families Lactobacillaceae, Pasteurellaceae, Alcanivoracaceae, Acutalibacteraceae, Peptostreptococcaceae_256921, Exiguobacteraceae, Coprobacillaceae, Bacillaceae_H_289398, Burkholderiaceae_A_595427 in patients with positive ART outcomes. When analyzing the urethral microbiome using high-throughput sequencing, no significant differences in alpha-diversity indices were shown. We also found significant differences (p<0.05) in the frequency of occurrence of the Streptococcaceae family, and they were more common in patients with negative ART outcomes. Meanwhile, representatives of the Enterococcaceae and Brevibacteriaceae families were more common in patients with positive ART outcomes. Conclusions. It is obvious that changes in the microbiota of the genital tract have a specific effect on the reproductive system, and correction of abnormal microbiomes can improve reproductive outcomes. © 2025 Elsevier B.V., All rights reserved.