DNA integrity in human spermatozoa: relationships with semen quality

Area of Science:

• Reproductive biology
• Andrology
• Spermatozoa research

Background:

• Conflicting literature exists on sperm DNA damage in infertile males.
• Sperm DNA fragmentation is a potential contributor to male infertility.
• Understanding DNA damage mechanisms is crucial for fertility treatments.

Purpose of the Study:

• To investigate the prevalence and impact of sperm DNA damage in infertile men.
• To correlate DNA fragmentation with semen quality parameters.
• To explore the relationship between DNA damage, reactive oxygen species (ROS), and antioxidant potential.

Main Methods:

• Semen analysis using World Health Organization (WHO) guidelines and computer-assisted sperm analysis (CASA).
• Sperm DNA fragmentation assessed via comet assay, in situ nick translation (ISNT-decondensed), and ISNT-condensed assays.
• Measurement of reactive oxygen species (ROS) and total reactive antioxidant potential (TRAP) in seminal plasma.

Main Results:

• Infertile men showed significantly lower semen quality and higher sperm DNA damage compared to normozoospermic donors.
• DNA fragmentation, measured by all three assays, strongly correlated negatively with sperm concentration.
• Sperm motility and ROS generation were also significantly related to DNA damage levels.

Conclusions:

• A substantial percentage of infertile men present with increased ejaculated sperm DNA damage.
• Sperm DNA fragmentation is a key factor associated with reduced semen quality in male infertility.
• These findings highlight the clinical relevance of assessing sperm DNA integrity in infertile populations.