The effects of antioxidant supplementation during Percoll preparation on human sperm DNA integrity

The integrity of sperm DNA is crucial for the maintenance of genetichealth. A major source of damage is reactive oxygen species (ROS)generation; therefore, antioxidants may afford protection to sperm DNA. Theobjectives of the study were, first, to measure the effects of antioxidantsupplementation in vitro on endogenous DNA damage in spermatozoa using thesingle cell gel electrophoresis (comet) assay and, second, to assess theeffect of antioxidant supplementation given prior to X-ray irradiation oninduced DNA damage. Spermatozoa from 150 patients were prepared by Percollcentrifugation in the presence of ascorbic acid (300, 600 microM), alphatocopherol (30, 60 microM), urate (200, 400 microM), or acetyl cysteine (5,10 microM). DNA damage was induced by 30 Gy X-irradiation. DNA strandbreakage was measured using the comet assay. Sperm DNA was protected fromDNA damage by ascorbic acid (600 microM), alpha tocopherol (30 and 60microM) and urate (400 microM). These antioxidants provided protection fromsubsequent DNA damage by X-ray irradiation. In contrast, acetyl cysteine orascorbate and alpha tocopherol together induced further DNA damage.Supplementation in vitro with the antioxidants ascorbate, urate and alphatocopherol separately has beneficial effects for sperm DNA integrity.