Effect of NOX5 activity on human sperm viability and motility

Background: The presence of NADPH oxidase 5 (NOX5) on human sperm was shown. Protein kinase C (PKC) activates this enzyme and increases reactive oxygen species (ROS) production. PMA as PKC activator and DPI (NOX inhibitor) were used to understand the role and importance of NOX5 in sperm ROS generation, motility and viability.Methods: Normal semen samples (n=20) were washed and divided into four groups; control, solvent (DMSO), PMA (100nM), and DPI (1μM). After 30 minutes incubation, sperm motility was analyzed by VT SPERM 3.1 and the viability was assessed by Eosin staining. ROS assessment was done by chemiluminescence method during 30 min.Result: Our results showed a significant decrease in motility and viability in PMA group compared with 3 other groups. The amount of ROS production was increased in PMA group and decreased when NOX5 activity was inhibited by DPI. (P < 0.05)Conclusion: It has been shown that activation of PKC caused sperm hyperactivation, but we showed that 30 minutes exposure of sperm to PMA, had a reverse effect which may be because of NOX5 activation and excess ROS production. According to reduction of ROS production after exposure to DPI, and the importance of low level of ROS in sperm normal function, we concluded that NOX5 is important in normal human sperm physiology.

کلیدواژه ها:

NOX5 ، PKC ، Human sperm