Ovine sperm DNA oxidation quantification using an 8-OHdG immunodetection assay

Area of Science:

• Reproductive Biology
• Molecular Biology
• Oxidative Stress Research

Background:

• DNA damage from oxidative stress is a critical factor in male fertility.
• Detecting oxidative DNA damage in ruminant sperm is challenging due to high DNA compaction.
• 8-hydroxy-2 -deoxyguanosine (8-OHdG) is a key biomarker for oxidative DNA damage.

Purpose of the Study:

• To optimize the 8-hydroxy-2 -deoxyguanosine (8-OHdG) immunodetection assay for quantifying DNA damage in ram sperm.
• To assess the effectiveness of 8-OHdG immunodetection for detecting oxidative stress-induced DNA damage, particularly in compacted ruminant sperm.
• To compare the 8-OHdG assay with the Sperm Chromatin Structure Assay (SCSA®).

Main Methods:

• Cryopreserved ram semen samples were analyzed using an 8-OHdG immunodetection assay via flow cytometry.
• Two primary antibody incubation times (30 minutes vs. overnight at 4°C) were evaluated.
• Results were compared with the Sperm Chromatin Structure Assay (SCSA®) and oxidation controls.

Main Results:

• No significant differences in 8-OHdG detection were found between 30-minute and overnight incubation periods.
• Overnight incubation showed a tendency towards increased non-specific secondary antibody binding.
• Significant differences in DNA oxidation were observed between individual rams and oxidation controls (H2O2/FeSO4).

Conclusions:

• The 8-OHdG immunodetection assay is a viable method for quantifying DNA oxidation in ram sperm.
• The assay can detect DNA damage induced by significant oxidative stress.
• Optimized protocols can enhance the detection of oxidative DNA damage in ruminant sperm.