Redox status of equine seminal plasma reflects the pattern and magnitude of DNA damage in sperm cells.

This research conducted on horse semen provides evidence that the antioxidant status of the seminal fluid can influence the amount and type of DNA damage in sperm cells.

Study Design and Participants

• The team of researchers included 23 stallions in their study, collecting samples of their seminal plasma for evaluation.

Methods

• They analyzed the antioxidant capacity of the seminal plasma, using the ABTS(•+) decolorization assay, and measured the thiol content, which are organic compounds containing sulfur.
• In addition, they assessed the DNA damage in sperm cells using various scientific techniques such as 8-oxoG immunostaining, TUNEL reaction, and the comet assay. These methods are reliable means to detect and measure molecular damage in the DNA strands of sperm cells.

Findings

• The researchers found a significant correlation between the total antioxidant capacity and thiol content of the seminal plasma, and the extent of DNA damage in the sperm cells.
• More importantly, they observed that a low redox status in the seminal fluid has a strong correlation with the 8-oxoG levels in sperm cells.
• The 8-oxoG is a byproduct of DNA oxidation and its presence suggest that the seminal antioxidant capacity predominantly affects the formation of single strand DNA breaks in the sperm cells. This means that a weak antioxidant defense in seminal plasma may lead to increased DNA damage in sperm cells, therefore affecting sperm quality.

Conclusion and Implications

• The researchers concluded their paper by suggesting that the redox status – a measure of antioxidant and oxidant balance – of seminal plasma, could be an additional crucial parameter for evaluating semen quality.
• This is alongside standard analysis of sperm count and morphology, to improve the quality evaluation of equine semen.
• The study underscores the importance of maintaining a healthy redox balance in the seminal plasma to ensure the integrity of the genetic material carried by the sperm cells.