Leucocytes and intrinsic ROS production may be factors compromising sperm chromatin condensation status
Considering that the final protection of the DNA against major assaults in terms of chromatin condensation is finalised in the epididymis, it is not known how sperm production of reactive oxygen species (ROS) and inflammatory processes can contribute to protamine deficiency that is predetermined in the testes. Therefore, this study aimed at investigating relationships between poor chromatin condensation, morphology, ROS production, DNA damage and the impact of the presence of leucocytes. In 70 patients, sperm DNA status was determined using TUNEL and chromomycin A3 (CMA3) assays, and ROS-production by means of dihydroethidine. Morphology was evaluated according to strict criteria. The percentage of CMA3-positive spermatozoa and leucocyte concentration (r = 0.178, P = 0.0377) as well as percentage of ROS-positive spermatozoa (r = 0.3010; P = 0.012) correlated significantly. Particularly, patients with leucocyte counts >0.5 × 106 ml-1 exhibited higher CMA3 positivity. No association was found between CMA3 positivity, TUNEL positivity and sperm morphology. While P- (poor prognosis: 0-4% normal morphology) and G-pattern (good prognosis: 5-14% normal morphology) morphology did not differ regarding chromatin condensation, P-pattern patients had a significantly higher percentage of DNA fragmentation (P = 0.0323). As oxidative stress is associated with disturbed chromatin condensation, results suggest that the idea that under-protamination of sperm DNA will automatically lead to DNA fragmentation might have to be revisited. © 2010 Blackwell Verlag GmbH.