Testicular microbiome in azoospermic men —first evidence of the impact of an altered microenvironment

AbstractSTUDY QUESTIONGiven the relevant role of the extracellular microenvironment in regulating tissue homeostasis, is testicular bacterial microbiome (BM) associated with germ cell aplasia in idiopathic non-obstructive azoospermia (iNOA)?SUMMARY ANSWERA steady increase of dysbiosis was observed among testis with normal spermatogenesis vs. iNOA with positive sperm retrieval and iNOA with complete germ cell aplasia.WHAT IS KNOWN ALREADYTissue-associated BM has been reported to be a biologically important extracellular microenvironment component for numerous body habitats, but not yet for the human testis.STUDY DESIGN, SIZE, DURATIONCross-sectional study, investigating tissue-associated BM in the testis of (i) five men with iNOA and negative sperm retrieval at microdissection testicular sperm extraction (microTESE); (ii) five men with iNOA and positive sperm retrieval at microTESE; and (iii) five normozoospermic men upon orchiectomy. Every testicular specimen was histologically classified and analyzed in terms of bacterial community.PARTICIPANTS/MATERIALS, SETTING, METHODSMassive ultra-deep pyrosequencing was applied to investigate testis microbiome. Metagenome was analyzed using Quantitative Insights Into Microbial Ecology (QIIME). Tissue-associated bacterial load was quantified by digital droplet PCR.MAIN RESULTS AND THE ROLE OF CHANCENormozoospermic men showed small amounts of bacteria in the testis, withActinobacteria,Bacteroidetes,Firmicutes Proteobacteria as the dominat...
Source: Human Reproduction - Category: Reproduction Medicine Source Type: research