Low expression of glycoprotein subunit 130 in ejaculated spermatozoa from asthenozoospermic men

Previous studies showed that interleukin-6 (IL-6) was expressed in human Leydig and Sertoli cells and that it inhibited sperm motility. The aim of this study was to compare the expression of IL-6, IL-6R, and GP130 in ejaculated spermatozoa between normozoospermic and asthenozoospermic men. Human spermatozoa in the semen were purified by Percoll gradient technique to separate the seminal plasma and other round cells. RT-PCR, immunocytochemistry, and Western blot were used to detect the expression of IL-6, IL-6R, and GP130 in spermatozoa. With RT-PCR, only GP130 mRNA but not IL-6 and IL-6R mRNA was expressed in human ejaculated spermatozoa. The expression of GP130 mRNA was significantly lower in asthenozoospermic men than in normozoospermic men. The protein expression of GP130 was further confirmed by both immunocytochemistry and Western blot. Again, GP130 protein levels were significantly lower in asthenozoospermic men than in normozoospermic men. The results suggested that the decreased expression of GP130 in ejaculated spermatozoa could be associated with low sperm motility in asthenozoospermic men.