Effects of biovar I and biovar II of ureaplasma urealyticum on sperm parameters, lipid peroxidation, and deoxyribonucleic acid damage in male infertility.

OBJECTIVE

To reveal the impact of 2 biovars of Ureaplasma urealyticum on the sperm of infertile men by producing reactive oxygen species (ROS).

METHODS

A total of 223 infertile and 146 fertile men were recruited into the study. Standard semen analysis was performed. Culturing and real-time polymerase chain reaction were used to identify biovars of U urealyticum in the semen. Semen ROS, malondialdehyde, and total superoxide dismutase levels were measured. Sperm nuclear deoxyribonucleic acid (DNA) damage was assessed of by sperm chromatin structure assay and single-cell gel electrophoresis.

RESULTS

Biovar II infection was more frequent in infertile men (P=.036). When compared with uninfected individuals, biovar II-infected men displayed decreases in spermatozoa concentration (P=.041); biovar II and mix-infected men displayed decreases in total motility (P=.015; P=.014, respectively) and increase in leukocyte counts (P=.004; P=.003, respectively). Except for total superoxide dismutase level, indicators for peroxide including ROS level, malondialdehyde level, DNA fragmentation index and high DNA stainable in sperm chromatin structure assay, and tail moment in single-cell gel electrophoresis exhibited the significant differences between both infected groups vs the uninfected group (P<05).

CONCLUSION

Compared with biovar I, biovar II is more likely to cause male infertility. Increased leukocyte counts, ROS level elevation, and subsequent spermatozoa membrane and DNA damage may be involved in this pathogenesis.