Relationship between phospholipase C zeta immunoreactivity and DNA fragmentation and oxidation in human sperm

ABSTRACT

OBJECTIVE: The study aimed to evaluate the feasibility and reproducibility of measuring phospholipase C zeta (PLCzeta) using immunostaining in human sperm and to investigate the relationship between PLCzeta immunoreactivity and DNA fragmentation and oxidation in human sperm. METHODS: Semen samples were obtained from participants (n=44) and processed by the conventional swim-up method. Sperm concentration, motility, normal form by strict morphology, DNA fragmentation index assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling method and immunofluorescent expression for 8-hydroxy-2'-deoxyguanosine (8-OHdG) and PLCzeta were assessed. RESULTS: When duplicate PLCzeta tests were performed on two sperm samples from each of the 44 participants, similar results were obtained (74.1+/-9.4% vs. 75.4+/-9.7%). Two measurements of PLCzeta were found to be highly correlated with each other (r=0.759, P<0.001). Immunoreactivity of PLCzeta was not associated with donor's age, sperm concentration, motility, and the percentage of normal form as well as DNA fragmentation index. However, immunoreactivity of PLCzeta showed a significant negative relationship with 8-OHdG immunoreactivity (r=-0.404, P=0.009). CONCLUSION: Measurement of PLCzeta by immunostaining is feasible and reproducible. Lower expression of PLCzeta in human sperm may be associated with higher sperm DNA oxidation status.