Effect of N-acetylcysteine on the sperm biochemical parameters and expression of HSPA70 and caspase-3 genes in asthenoteratospermic infertile males undergoing cryopreservation

Protecting sperm against oxidative reactions during cryopreservation is one of the supportive measures to enhance sperm quality and thus the success of ART. The present study aimed to investigate the effect of N-acetylcysteine (NAC) on the functional parameters of human sperm and to evaluate the apoptosis and expression of HSP70 and Caspase3 genes after cryopreservation. In this in vitro prospective study, 40 men referred to infertility center of ACECR, Qom were used. They were divided into two groups: the first group of men with normal WHO criteria and the second group of people with asthenoteratospermia, and was cryopreserved with sperm freeze supplemented with NAC at concentrations of 0.01, 0.02, 0.05, 0.1 and 0.25 mM. Semen samples were evaluated for sperm parameters including concentration, morphology, motility, viability, reactive oxygen species (ROS), apoptosis and expression of HSP70 and caspase 3 genes. Findings showed that NAC 0.02 and 0.05 mM significantly increased sperm motility, however it was decreased by NAC 0.025 mM compared to control group (P˂0.05). Except for NAC 0.25 mM, all doses of NAC especially 0.05 mM increased sperm viability (P˂0.05). Interestingly, the same results were observed about normal sperm morphology, concentrations and production of reactive oxygen species (ROS). Also, all doses of NAC especially 0.02 mM and 0.05 mM significantly reduced the apoptosis and expression of HSP70 and caspase3 genes. Overall, it is determined that NAC supplementation prior to cryopreservation dramatically enhances the quality of sperm and decreases the freezing-shock side effects.