Seminal 5'tRF-Glu-CTC as a Biomarker for Oligozoospermia and ART Outcome Prediction.

Background: Epigenetic mechanisms influencing sperm production and function are closely linked to male infertility. Among these, tRNA-derived fragments have recently been identified as important modulators of cellular stress responses and gene expression. The purpose of this study was evaluate the potential role of 5'tRF-Glu-CTC in the context of assisted reproductive technologies (ART) outcomes by comparing its differential expression in the seminal plasma of oligozoospermic and normozoospermic infertile men.

Results: Total RNA was extracted from seminal plasma, and 5'tRF-Glu-CTC expression was measured by qRT-PCR. Sperm DNA fragmentation index (DFI) was assessed via the TUNEL assay. The results revealed significantly elevated 5'tRF-Glu-CTC expression in the oligozoospermic group compared to the normozoospermic group (15.58 ± 4.34 vs. 12.53 ± 4.99; fold change: 1.692; P = 0.024). Sperm DFI showed a significant negative correlation with both the progressive motile sperm (ρ = -0.537, P = 0.015) and the total progressive motile sperm count (ρ = -0.509, P = 0.026). However no significant differences in DFI was observed between the oligozoospermic and control groups (P > 0.05). Analysis of ART outcomes revealed that male partners of couples who achieved pregnancy had lower mean 5'tRF-Glu-CTC expression and DFI, although these differences did not reach statistical significance (P > 0.05).

Conclusions: These results suggest that 5'tRF-Glu-CTC might be serve as a potential biomarker and could play a role in the pathophysiology of oligozoospermia.