Association between semen microbiome disorder and sperm DNA damage

Area of Science:

• Reproductive Biology
• Microbiome Research
• Male Infertility Diagnostics

Background:

• Sperm DNA fragmentation index (DFI) is a key biomarker for male infertility and poor reproductive outcomes.
• Previous studies suggest a correlation between seminal microbiome composition and sperm DNA integrity.
• The precise mechanisms by which the microbiome influences sperm DNA damage remain largely unelucidated.

Purpose of the Study:

• To investigate the role of the seminal microbiome and its metabolic activity in high sperm DNA fragmentation index (HDFI).
• To identify specific microbial profiles and metabolites associated with HDFI.
• To explore the potential of the seminal microbiome as a therapeutic target for HDFI.

Main Methods:

• Combined 16S rRNA sequencing for microbial profiling.
• Untargeted metabolomics for identifying key metabolites.
• Comparative analysis of semen samples from HDFI patients and controls.

Main Results:

• Specific microbial profiles were found to contribute to HDFI.
• *Lactobacillus iners* was significantly enriched in HDFI patients.
• Enrichment of acetyl-CoA fermentation to butanoate II and purine nucleobase degradation I pathways was observed in HDFI samples, with butanoate implicated in sperm DNA damage.

Conclusions:

• The seminal microbiome plays a significant role in sperm DNA fragmentation.
• *Lactobacillus iners* and butanoate metabolism are potential contributors to HDFI.
• Targeting the seminal microbiome offers a novel therapeutic strategy for HDFI patients.