Early apoptotic changes in human spermatozoa and their relationships with conventional semen parameters and sperm DNA fragmentation.
OBJECTIVE
To investigate whether early apoptotic changes in spermatozoa can be significant markers for sperm quality.


METHODS
Two early apoptotic changes in the semen of 56 men were assessed using Annexin V (AN)/propidium iodide (PI) staining for phosphatidylserine externalization and JC-1 staining for mitochondrial membrane potential (MMP). The results were compared with conventional semen parameters and DNA fragmentation identified using the TUNEL assay.


RESULTS
The different labeling patterns in the bivariate Annexin V/PI analysis identified four distinctive spermatozoa populations. The percentage of AN(-)/PI(-) spermatozoa positively correlated with conventional semen parameters and MMP, but negatively correlated with TUNEL (+) spermatozoa. As for the AN(-)/PI(+) fraction, we found an opposite result in comparison to AN(-)/PI(-) spermatozoa. The level of early apoptotic AN(+)/PI(+) spermatozoa negatively correlated with MMP and sperm motility. The level of late apoptotic AN+/PI+ spermatozoa negatively correlated with conventional semen parameters and MMP, and positively correlated with TUNEL (+) spermatozoa. MMP positively correlated with conventional semen parameters, but negatively correlated with TUNEL (+) spermatozoa.


CONCLUSIONS
Although early apoptotic AN+/PI(-) spermatozoa only negatively correlates with sperm motility, the differences in proportion of each subpopulation of spermatozoa (especially, the percentage of AN(-)/PI(-) spermatozoa), and decreased MMP might be significant markers for diagnosing male infertility. They possibly bring additional information to predict the outcome of in vitro fertilization.
Zhang
Hao-Bo
HB
Center for Reproductive Medicine, Provincial Hospital-Shandong University, 324 Jing-5-Wei-7 Road, Jinan, China.
Lu
Shao-Ming
SM
Ma
Chun-Yan
CY
Wang
Li
L
Li
Xiao
X
Chen
Zi-Jiang
ZJ
D000328:Adult; D017209:Apoptosis / Q000502:physiology*; D004247:DNA / Q000502:physiology; D053938:DNA Fragmentation; D006801:Humans; D007248:Infertility, Male / Q000175:diagnosis; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000502:physiology*; D012661:Semen / Q000502:physiology*; D013094:Spermatozoa / Q000166:cytology* / Q000502:physiology*
D004247:DNA