Differential expression of ODF1 in human ejaculated spermatozoa and its clinical significance

OBJECTIVE To compare the expressions of ODF1 (outer dense fiber of the sperm tail 1) in ejaculated spermatozoa from normozoospermic and asthenozoospermic men with low sperm motility. METHODS Semen analyses were performed on the semen samples obtained from normozoospermic (n=20) and asthenozoospermic (n=20) volunteers according to the WHO criteria. To rule out the contamination of germ cells and leucocytes, the human ejaculated spermatozoa were purified by a discontinuous Percoll density gradient centrifugation. RT-PCR and Western blot were used to detect the expressions of ODF1 in the spermatozoa from the two groups. RESULTS RT-PCR showed that the expression of ODF1 mRNA was significantly lower in the spermatozoa from the asthenozoospermic patients than in those from the normozoospermic men (1.35 +/- 0.25 vs. 2.79 +/- 0.28, P < 0.05). Western blot confirmed the results from RT-PCR and revealed an obviously decreased expression of ODF1 in the spermatozoa of the asthenozoospermic patients, with statistically significant difference from the normozoospermic group (1.44 +/- 0.26 vs. 3.64 +/- 0.34, P < 0.05). CONCLUSION The expression of ODF1 was significantly decreased in the ejaculated spermatozoa of asthenozoospermic men, which might be responsible for low sperm motility.