DNA fragmentation, mitochondrial dysfunction and chromosomal aneuploidy in the spermatozoa of oligoasthenoteratozoospermic males

Purpose This study determined the incidence of sperm nuclear DNA fragmentation, mitochondrial dysfunction, and chromosomal aneuploidy. The results were correlated with the semen analysis parameters and fertilization rates. Methods Semen samples from 10 men showing oligoasthenoteratozoospermia OAT and undergoing ICSI treatment were analyzed. Another semen samples from 10 men showing normozoospermia and undergoing IVF treatment were analyzed for comparison. The samples were prepared using a two-step discontinuous Percoll gradient 80%-50% and analyzed using a Hamilton-Thorne Integrated Visual Optical System IVOS Sperm Analyzer. DNA fragmentation was detected with a terminal deoxynucleotidyl transferase-mediated dUTP nick end label TUNEL assay. Functional integrity of mitochondria was detected using an Apoalert™TM Mitochondrial Membrane Sensor Kit. Chromosomal aneuploidy was assayed by fluorescence in situ hybridization. Results Higher sperm DNA fragmentation rate 18.8% vs. 2.8%, mitochondrial dysfunction rate 24.9% vs. 5.7%, and chromosomal aneuploidy rate 0.12% vs. 0.06% were found in the oligoasthenoteratozoospermic patients in comparison with the normozoospermic patients. Conclusions The result indicates that spermatozoa from oligoasthenoteratozoospermic patients contain greater DNA fragmentation, mitochondrial dysfunction, and chromosomal aneuploidy. Because extremely poor semen samples are the indication for ICSI treatment, the result indicates the importance of selecting good quality sperm for oocyte injection.